Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1038/s41428-022-00752-7

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Other Link： https://www.nature.com/articles/s41428-022-00752-7

Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1002/pi.6440

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/pi.6440

Publishing type：Research paper (scientific journal)   Publisher：The Chemical Society of Japan  

DOI： 10.1246/cl.220333

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.polymer.2022.125092

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Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society (ACS)  

DOI： 10.1021/acs.macromol.2c00596

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Publishing type：Research paper (scientific journal)  

The authors regret incorrect Table 3. The revised Table with the changes is available below. [Table presented] The authors would like to apologise for any inconvenience caused.

DOI： 10.1016/j.polymer.2022.124726

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Absolute asymmetric polymerizations, which do not need chiral compounds, are very limited. In addition, they involve spontaneously formed supramolecular compounds, or they need circularly polarized light, and the resulting polymers are often insoluble showing no chiral information at the molecular level. Here we have achieved five kinds of real absolute asymmetric polymerizations of achiral acetylene monomers showing no CD in solution to yield soluble high MW chiral polymers showing CD peaks in solution. These polymerizations did not contain spontaneously formed chiral crystals of monomers or did not use circularly polarized light. A new mechanism we propose here for this new unusual polymerization will give us clues to a better understanding of the reason for the homochirality of our world.

DOI： 10.1016/j.polymer.2022.124673

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1002/chir.23404

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/chir.23404

Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.polymer.2021.124347

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Oxygen/nitrogen permselective membranes play particularly important roles in fundamental scientific studies and in a number of applications in industrial chemistry, but have not yet fulfilled their full potential. Organic polymers are the main materials used for such membranes because of the possibility of using sophisticated techniques of precise molecular design and their ready processability for making thin and large self-supporting membranes. However, since the difference in the properties of oxygen and nitrogen gas molecules is quite small, for example, their kinetic diameters are 3.46 Å and 3.64 Å, respectively, the architectures of the membrane macromolecules should be designed precisely. It has been reported often that oxygen permeability (PO2) and oxygen permselectivity (α = PO2/PN2) have trade-off relationships for symmetric membranes made from pure polymers. Some empirical upper bound lines have been reported in (ln α − ln PO2) plots since Robeson reported an upper bound line in 1991 for the first time. The main purpose of this review is to discuss suitable macromolecular structures that produce excellent oxygen/nitrogen permselective membranes. For this purpose, we first searched extensively and intensively for papers which had reported α and PO2 values through symmetric dense membranes from pure polymers. Then, we examined the chemical structures of the polymers showing the top performances in (ln α − ln PO2) plots, using their aged performances. Furthermore, we also explored progress in the molecular design in this field by comparing the best polymers reported by 2013 and those subsequently found up to now (2020) because of the rapid outstanding growth in this period. Finally, we discussed how to improve α and PO2 simultaneously on the basis of reported results using not only symmetric membranes of pure organic polymers but also composite asymmetric membranes containing various additives.

DOI： 10.3390/polym13173012

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Publishing type：Research paper (scientific journal)   Publisher：The Chemical Society of Japan  

DOI： 10.1246/cl.210341

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Publishing type：Research paper (scientific journal)   Publisher：The Chemical Society of Japan  

DOI： 10.1246/cl.210306

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.polymer.2021.123857

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.polymer.2021.123900

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Three new phenylacetylene monomers having one or two carbamate groups were synthesized and polymerized by using (Rh(norbornadiene)Cl)2 as an initiator. The resulting polymers had very high average molecular weights (Mw) of 1.4–4.8 × 106, with different solubility and membrane-forming abilities. The polymer having two carbamate groups and no hydroxy groups in the monomer unit showed the best solubility and membrane-forming ability among the three polymers. In addition, the oxygen permeability coefficient of the membrane was more than 135 times higher than that of a polymer having no carbamate groups and two hydroxy groups in the monomer unit with maintaining similar oxygen permselectivity. A better performance in membrane-forming ability and oxygen permeability may be caused by a more extended and flexible cis-transoid conformation and lower polarity. On the other hand, the other two new polymers having one carbamate group and two hydroxy groups in the monomer unit showed lower performances in membrane-forming abilities and oxygen permeabilities. It may be caused by a very tight cis-cisoid conformation, which was maintained by intramolecular hydrogen bonds.

DOI： 10.3390/membranes10090199

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Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society (ACS)  

DOI： 10.1021/acsmaterialslett.0c00178

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Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society (ACS)  

DOI： 10.1021/acsapm.9b01111

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.polymer.2019.122081

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/polym11111877

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier B.V.  

Six new silicon-containing phenylacetylenes having short oligosiloxane substituents with different sizes and shapes have been synthesized. Homopolymerization of the monomers yielded the corresponding homopoly(substituted phenylacetylene)s with high molecular weights and good solubility. These comb-shaped homopolymers gave self-standing membranes whose PO2 and PO2 /PN2 could be measured. We discuss the effect of the chemical structures on their membrane performances together with the other seven related polymers we synthesized before and commercially available cross-linked polydimethylsiloxane (PDMS). While the homopolymers with linear oligodimethylsiloxanes (ODMS) show very high PO2 values which are higher than PDMS, the homopolymers with branched ODMS show high PO2 /PN2 values which are close to that of poly(phenylacetylene) (poly(PA)) and, in addition, had ten times higher PO2 than poly(PA). Introduction of the branched spherical ODMS substituents increases PO2 without any drop of PO2 /PN2 and introduction of the linear ODMS substituents increases PO2 largely which is higher than that of PDMS. It was found that the chemical structures, i.e., the shapes of the ODMS substituents were more important than that of composition for determining their performance as oxygen permselective membrane materials. In conclusion, oxygen permeation could be tuned by changing sizes and shapes of the ODMS side groups.

DOI： 10.1016/j.memsci.2018.04.031

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Ltd  

A diphenylacetylene monomer carrying a dimesitylboryl functional group was newly synthesized and polymerized by heating the toluene solution at 80 °C, using TaCl5–n-Bu4Sn as a catalyst. A polydiphenylacetylene (PDPA) derivative was obtained in high yield despite the presence of the heteroatom
the polymer had an extremely high weight-average molecular weight of 1.27 × 106 gmol−1 and readily dissolved in organic solvents. This polymer was highly resistant to heat and existed in an amorphous, glassy state at room temperature. Unlike the usual PDPA derivatives, the fluorescence (FL) maximum for this derivative appeared at 526 nm through efficient intramolecular energy transfer from the side dimesitylboryl groups to the polyene backbone upon excitation at a very short wavelength of 320 nm, indicating an extremely large Stokes shift of 206 nm. Moreover, the polymer showed considerably higher FL efficiency of 49.3% in a tetrahydrofuran solution and 19.1% in a film as compared to the usual PDPA derivatives. This polymer reacted with fluoride ions to exhibit critical changes in absorption and FL emission, which were expressed by an exponential and a Gaussian functional equation, respectively.

DOI： 10.1016/j.polymer.2018.06.044

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1038/s41428-018-0045-7

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Other Link： http://www.nature.com/articles/s41428-018-0045-7.pdf

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Nature Publishing Group  

For THF solutions of an optically active helical poly[3,5-bis(hydroxymethyl)phenylacetylene] derivative bearing a biphenyl group, photoexcitation of the terphenyl moiety at 300 nm led to photoluminescence at 390 nm. On the other hand, the photoluminescence resulting from excitation at 280 nm caused dual emission at 310 and 390 nm, whose intensities were tuned by the polar-solvent stimuli which induced the collapse of the intramolecular stack structure of the side groups, and the change in the emission wavelength accompanied disappearance of the optical activity.

DOI： 10.1038/s41428-018-0045-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Ltd  

Selective photocyclic aromatization (SCAT) of cis–cisoid helical poly(phenylacetylene) derivatives was investigated during the in situ photodegradation in a film. An infrared absorption peak appeared at ∼1700 cm−1 owing to the overtone vibration of the 1,3,5-trisubstituted benzene and the peak at 1060 cm−1 due to the cis C=C bending of the main chain decreased, indicating occurrence of SCAT. Simultaneously, the polymer film became emissive in visible region during SCAT. The fluorescence (FL) quantum efficiency was approximately 0.92% in the film and not so much high relative to usual fluorophores. The FL emission disappeared in an instant when the decomposition product dissolved in a solvent. The FL lifetime of the polymer film increased with photodegradation. These all indicated the occurrence of excimer emission. A finely resolved FL image pattern was readily obtained using a photomask.

DOI： 10.1016/j.dyepig.2017.10.035

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley-VCH Verlag  

A brand new, soluble quadruple-stranded copolymer is synthesized by using a self-template polymer from a new monomer. In addition, another very unique quadruple-stranded copolymer having a π−π stacking supramolecular polymer main chain is synthesized by selective photocyclic aromatization of the quadruple-stranded copolymer. The two quadruple-stranded copolymers gave self-standing membranes.

DOI： 10.1002/marc.201700556

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Since highly selective photocyclic aromatization (SCAT) of poly(substituted acetylene) s yields quantitatively the corresponding 1,3,5-trisubstituted benzene derivatives, the SCAT products were applied for quantitative determination of microstructures of copoly(substituted acetylene) s by NMR (nuclear magnetic resonance). By this SCAT-NMR method for two copolymers of two different types of substituted acetylenes, quantitative analysis for microstructures, i. e., triad distributions and compositions, have been achieved successfully under mild conditions, although they could not be obtained from the NMR of the original copolymers because of their broad and overlapped peaks.

DOI： 10.1246/cl.170697

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

In order to estimate oxygen permselectivities through a supramolecular polymer membrane for the first time, we prepared three kinds of composite membranes consisting of a supramolecular polymer membrane and a conventional organic polymer membrane. Supramolecular polymer membranes were prepared by using highly selective photocyclic aromatization of poly(substituted acetylene)s. It was found that the supramolecular polymer membrane had oxygen permselectivity (alpha = P-O2/P-N2) around three in spite of its low molecular weight. (C) 2017 Published by Elsevier Ltd.

DOI： 10.1016/j.polymer.2017.08.066

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Chiral compounds play a vital role in our lives because we are made up of chiral polymers. A strict rule of chirality synthesis is "to obtain one enantiomer of a new chiral product, one enantiomer of a chiral source is needed". If two enantiomers can be synthesized using a single chiral compound, we can both break the above rule and open up a more efficient route to useful chiral materials using a cheaper chiral source. Here we report the first example of double reversals of enantioselectivity in catalytic asymmetric polymerization of achiral monomers using a single isomer of simple chiral compounds as cocatalyst. Furthermore, we achieved this by changing only one achiral condition, that is, the amount of the chiral cocatalyst, without any other changes in the polymerization conditions. As a result, we easily and directly synthesized (+)- or (-)-polymer using a single chiral compound as a cocatalyst.

DOI： 10.1021/acs.macromol.7b01671

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Novel well-defined complex,polymers, polymers of acetylene type macronionomers having silylene-vinylene-phenylene-ethynylene hyper-branches, investigated as a new class of subnanoporous oxygen permselective membrane materials, were synthesized very easily by one-pot Simultaneous two-mode homopolymerization of a single monomer with a single catalyst. For this "simultaneous polymerization" we synthesized AB(2)-type monomers (1,3-bis(dimethylsilyl)phenylacetylenes) containing one terminal triple bond and two Si-H groups. The resulting poly(hyperbrancIed mactornonomer)s had high molecular weights, low densities, high solubility, and good self-membrane forming ability. They had higher oxygen permselectivities (a = P-O2/P-N2) than any other reported polymers having similar oxygen permeabilities (P-O2). These excellent polymer membranes could be obtained only by the simultaneous polymerization. In the one-pot simultaneous polymerization, the two different modes of polymerizations, i.e., addition polymerization of the triple bond and polyaddition of the triple bond and two SiH groups in the single monomer, occurred simultaneously by using one catalytic system, i.e., [Rh(norbornadiene)Cl](2)/various amines. The ratio of the branches (RB), i.e., the addition polymerization and the polyaddition, could be controlled by changing the amine cocatalysts. Their oxygen permselectivities could be adjusted by controlling the polymer structures including RB.

DOI： 10.1021/acs.macromol.7b01458

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Two poly(diphenylacetylene) derivatives containing identical chiral pinanyl groups on the para- and meta-positions of the side phenyl ring were prepared, and their circular dichroism (CD) and photoluminescence (PL) spectra were compared. The magnitudes of circular polarization (g(CD)) of the para- and meta-polymers were determined to be 3.1 x 10(3) and 1.4 x 10(3), respectively. The PL quantum yield (PLQY) of the para-polymer was much greater (27.8%) than that of the meta-polymer (2.61%). When the two polymers were annealed at 80 C in toluene, their CD spectra were remarkably enhanced and reached equilibrium at g(CD) values of 9.6 x 10(3) and 6.0 x 10(3), respectively. The para-polymer was kinetically more favored for the CD enhancement as known from the fact that the activation energies for the reactions of para- and meta-polymers were determined to be 88 and 187 kJ mol(1), respectively. The PLQYs of both polymers were unaffected by annealing.

DOI： 10.1021/acs.macromol.7b01283

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

A PDPA derivative with a long alkyl side chain connected directly onto the backbone (1) was synthesized and compared to a corresponding polymer with a silylene linkage between the side chain and the backbone (2). Polymers 1 and 2 showed similar solubilities: both polymers dissolved well in organic solvents such as toluene, THF, and chloroform but not in polar solvents such as DMF and alcohols. When cast from toluene solutions, smooth and transparent films were readily obtained. Thermogravimetric analysis showed that 1 was more thermally stable than 2 owing to the absence of the relatively weak silylene linkage. Differential scanning calorimetry showed that 1 exhibited a local thermodynamic relaxation due to the long alkyl side chains at a higher temperature than 2. In photoluminescence spectroscopy, 1 was found to be more emissive, with quantum yields being as high as 63.1 and 27.4% in solution and films, respectively, while those of 2 were 49.4 and 20.6%. Consequently, 1 was more thermally stable, stiffer, and more emissive than 2. (C) 2017 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2017.07.011

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

New types of multi-bridged copolymers were designed and examined as oxygen permselective membrane materials. The multi-bridged copolymers were synthesized by imine metathesis reactions between N-imine (synthetic equivalent of amine)containing poly(substituted acetylene)s and C-imine (synthetic equivalent of aldehyde)-containing poly(substituted acetylene) s in the membrane state. The resulting copolymers maintained good self-membrane forming ability. The introduction of multibridge structures enhanced both oxygen permselectivities and oxygen permeabilities simultaneously.

DOI： 10.1246/cl.161104

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Both cis- and trans-rich poly[p-(trimethylsilyl)phenylacetylene]s (PTM-SPAs) were synthesized using [Rh(norbornadiene)Cl](2)-TEA (TEA: triethylamine) and WCl6-Ph4Sn as catalysts, respectively. The Rh-based cis-rich polymer exhibited a remarkable fluorescence (FL) emission enhancement after thermal annealing (heating at 200 degrees C in N-2 atmosphere for 1 min), while the pristine polymer was almost entirely non-emissive. NMR and Raman spectroscopic studies clarified the occurrence of irreversible cis-trans isomerization under thermal annealing and suggested that the FL emission increased with an increase in the trans content of PTMSPA. Computer simulations of 12-mer model compounds clarified that the FL emission is a result of intramolecular excimers formed from side-on -stacking of phenyl groups, which is possible only along the backbone of the trans-based polymer.

DOI： 10.1080/15421406.2016.1277910

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Polydiphenylacetylene (PDPA) derivaitves consisting of different central atoms of C, Si, and Ge in the pendent group were comparatively investigated in normal, swollen, and acid-treated states. The Ge-containing PDPA was more emissive than the other two both in solution and in solid states. All the polymers showed emission enhancement in a swollen state: The PL quantum yields increased remarkably when swollen in an appropriate non-solvent. The Si and Ge atoms were easily removed from the polymer chain under acidic condition, as a result, the PL intensity was significantly decreased and the polymers turned to be insoluble in common organic solvents. Although the tert-butyl group of C-containing PDPA remained intact during the acid exposure, similar PL attenuation occurred.

DOI： 10.1080/15421406.2017.1338491

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS INC  

One of the authors discovered helix-sense-selective polymerization (HSSP) of an achiral substituted phenylacetylene which has two hydroxymethyl groups and a relatively hydrophobic substituent by using a chiral catalytic system in 2003. The one-handed helicity is stable and static in nonpolar solvents because it is maintained by intramolecular hydrogen bonds. Since the resulting polymer has extremely tight helicity in its main chain, it shows many interesting and unusual properties including highly selective photocyclic aromatization (SCAT). In this review, the discovery and development of the HSSP and SCAT reactions, and the properties and application of the resulting polymers prepared by HSSP and the resulting supramolecular polymers prepared by SCAT will be examined.

DOI： 10.1080/15583724.2016.1160930

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

By using a living one-handed helical cis-transoidal poly(chiral substituted phenylacetylene) as a polymer initiator (poly(I-n)), helix-sense-selective polymerization (HSSP) of an achiral phenylacetylene 2 having two hydroxy groups successfully afforded a diblock copoly(phenylacetylene) (copoly(I-n/2(m))) consisting of a dynamic one-handed helical cis-transoidal block and a static one-handed helical cis-cisoidal block. The formation of the diblock structure was confirmed by consumption of the chiral initiator, appearance of characteristic CD indicating the one handed helical cis-cisoidal block, and occurrence of the selective photocylic aromatization reaction in the cis-cisoidal block. Therefore, HSSP has been achieved by using the chiral alkenyl groups in the initiator as a chiral source for the first time. In addition, since the HSSP was achieved in spite of the long distance between the chiral initiation site and the propagating site, chiral teleinduction through the rigid and static one-handed helical cis-cisoidal block based on domino effects was confirmed.

DOI： 10.1021/acsmacrolett.6b00809

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

We synthesized six phenylacetylenes (RCOPAs, RSOPAs, and RSPAs) having a bulky fused polycyclic aliphatic group, which is adamantyl(Ad), pinanyl(Pi), or cholesteryl(Ch) via oxycarbonyl (CO) or oxydimethylsilyl( SO), and the other two phenylacetylenes having less or non-bulky substituents, i.e., menthyloxycarbonylphenylacetylene (MtCOPA) or ethoxydimethylsilylphenylacetylene (EtSOPA) (Et = Ethyl). The new monomers were polymerized and copolymerized with p-trimethylsilylphenylacetylene (SPA) by using catalyst [ Rh(nbd)Cl](2) (nbd = 2,5-norbornadiene) in trimethylamine to give soluble high molecular-weight polymers in relatively good yields. The resulting copolymers were fabricated to self-supporting membranes which had enough strength for separation membranes by solution casting method. As a result, we can discuss the relationship between bulky chemical structures and permeation behavior systematically for the first time. Oxygen permselectivities (PO2/PN2) of copolyRSOPAs having the bulky fused polycyclic aliphatic groups such as Ad and Pi were higher than those of copolyEtSOPAs. PO2/PN2 values of copolyRCOPAs were higher than those of polyRSOPAs when they had the same content of the identical bulky groups. The rigid spacer was effective for enhancing PO2/PN2. Among copolyRCOPAs with bulky fused polycyclic aliphatic groups, the copolymers with spherical substituents such as Pi and Ad groups showed higher PO2/PN2 values than those with a planer substituent i.e., Ch groups. PO2 values of copolyRSOPAs and copolyRCOPAs were 130-220 and 50-90 barrer, respectively. The flexible silyloxy spacers in RSOPAs were effective in enhancing their PO2 values. (C) 2016 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2016.07.023

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Two novel chiral well-defined rhodium complexes, Rh(cod)(L-Phe) (cod=1,5-cyclooctadiene, Phe=phenylalanine) and Rh(cod)(L-Val) (Val=valine) were synthesized, isolated by recrystallization, and characterized. The helix-senseselective polymerization (HSSP) of an achiral 3,4,5-trisubstituted phenylacetylene, p-dodecyloxy-m, m-dihydroxyphenylacetylene (DoDHPA) was examined by using the two Rh complexes as catalysts. These catalysts provided high molecular weight polymers (M-w 28 x 10(4)-45 x 10(4)) in about 40%-85% yields. The resulting polymers exhibited a bisignated CD signal at about 300 nm and a broad signal around 470 nm, indicating that they have preferential one-handed helical structure. The present catalysts achieved larger molar ellipticity up to [theta](310) = 13.0 x 10(4) deg cm(2)/dmol than those with binary chiral catalytic systems, [Rh(cod)Cl](2)/(L-phenylalaninol), [Rh(cod)Cl](2)/(L-valinol), and [Rh(nbd)Cl](2)/(R)-PEA. All these results manifest that the present, well-defined Rh complexes serve as excellent catalysts for the HSSP of DoDHPA. (C) 2016 Wiley Periodicals, Inc.

DOI： 10.1002/pola.28106

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Highly selective photocyclic aromatization (SCAT) of poly(substituted acetylene)s, which can quantitatively yield the corresponding 1,3,5-trisubstituted benzene derivative, was applied to quantitative determination of the microstructures of copoly(substituted acetylene)s. By GPC analysis of the SCAT products of the copolymers of two substituted acetylenes having substituents whose molecular weights were greatly different, some clear information regarding the microstructures, such as sequence (triad) distribution and composition, which could not be obtained from NMR because of their broad peaks, could be obtained successfully under a mild condition.

DOI： 10.1246/cl.160357

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A highly emissive, optically active poly(diphenylacetylene) derivative, NpSi*-PDPA, was synthesized by introducing a bulky chiral pendant group into the polymer chain. NpSi*-PDPA exists in a glassy state having a highly disordered and amorphous structure. Hence, the fractional free volume is quite high, i.e., 0.29. NpSi*-PDPA emits a green light in solution and a yellow light in film. This polymer is quite emissive, as the photoluminescence (PL) quantum yield is 56.1% in solution and 6.2% in film, and the PL lifetime is relatively long, 1.71 ns in solution and 1.05 ns in film. NpSi*PDPA shows the strongest circular dichroism (CD) signal at 384 nm, with a magnitude of circular polarization (g(CD)) of 0.90 x 10(-3) and an optical rotation of 110 degrees (4.30 X 10(-3) g mL(-1), in CHCl3). The CD intensity is significantly increased by annealing at 80 degrees C, reaching an equilibrium at g(CD) of 7.10 X 10(-3) after 72 h.

DOI： 10.1021/acsmacrolett.6b00184

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Commercially available molecular rotor (MR) compounds were recrystallized using chiral monoterpenes as solvents. The resulting crystals exhibited large circular dichroism signals with opposing signs according to the handedness of the chiral solvent used. X-ray crystallographic analysis showed that the chirality originated from asymmetric restriction of intramolecular rotation in the crystals. The crystals were also highly emissive due to restricted bond rotation, while solutions of the materials were almost nonemissive. The solvent-to-MR chirality transfer approach to. crystallization discussed herein should be a convenient, universal way to obtain highly emissive chiral crystals.

DOI： 10.1021/acs.cgd.6b00128

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A novel soluble well-defined ladder polysiloxane bridged by imido linkages having a high molecular weight was successfully synthesized via the corresponding supramolecular intermediate and was fabricated to a very flexible self-standing membrane. The membrane showed a better oxygen permselectivity than conventional linear polyorganosiloxanes. We directly observed the effect of the regular molecular-sized pores formed by the ladder structure on the oxygen permselectivity for the first time. This is the first report on gas permeability thorough a well-characterized ladder polymer.

DOI： 10.1246/cl.151196

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The chain rigidity, liquid crystallinity, absorptivity, and photoluminescence of a helical poly(phenylacetylene) derivative varied significantly depending on the solvent employed, owing to the conformational changes caused by the formation or destruction of intramolecular hydrogen bonds. The polymer chains were rigid and liquid crystalline when dissolved in such non-solvents as toluene and THF to show lower absorptivity and intramolecular excimer emission while the same polymer chains became flexible in piperidine having a high hydrogen-bonding acceptor strength to exhibit strong absorption in the visible region and the emission was significantly quenched.

DOI： 10.1039/c6ra01940d

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A novel achiral phenylacetylene having a bulky t-butyl group was synthesized and polymerized by a chiral catalytic system containing [Rh(nbd)Cl](2) (nbd: norbomadiene) and chiral amines to yield a one-handed helical polymer having a much higher g value than polymers with no bulky groups. Highly efficient helix-sense-selective polymerization has been achieved using a bulky monomer and a less bulky chiral cocatalyst.

DOI： 10.1246/cl.150863

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Poly(diphenylacetylene) membranes having perfluoroalkyl groups were quantitatively synthesized via a three-step membrane reaction, that is, desilylation (the 1st step), Williamson reaction (the 2nd step), and Click reaction (the 3rd step). The conversions of the all reactions were confirmed by IR. spectra and elemental analysis. Even though the reactions were carried out in membrane state, the conversions were fairly high. These high conversions are attributed to high swelling property of poly(diphenylacetylenes), including the extremely large fractional free volume. The gas permeability and thermal property of the perfluoroalkylated poly(diphenylacetylene) membranes were investigated. Polymer reactions are a very useful and powerful

DOI： 10.1246/cl.150841

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

We synthesized new 3,5-bis(hydroxymethyl)phenylacetylene (HPA) monomers connected with a rigid and linear pi-conjugated oligomer. The monomers were successfully polymerized with a rhodium catalyst [Rh(nbd)Cl](2) in the presence of chiral PEA to give the corresponding polymers. Helix-sense-selective polymerization proceeded for DBHPA. CD, UV, and WAXS spectroscopic studies revealed that the intramolecular hydrogen bonds of the polymers contributed to the stabilization of their helical conformation but the stability depended on the length of the rigid and linear pi-conjugated side group.

DOI： 10.1246/cl.150616

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

A novel phenylacetylene monomer having a perfluorinated alkyl group (M-F) was synthesized and polymerized in a chiral catalytic system to yield a one-handed helical polymer. The ability and efficiency of the chiral induction of the fluorine-containing monomer in the helix-sense-selective polymerization (HSSP) was much higher than those of a monomer having the corresponding alkyl group (M-H) we reported before. The resulting polymer P-F showed cis-cisoidal one-handed helical conformation, and was suitable for highly selective photocyclic aromatization (SCAT) to give a 2D surface modifier (T-F). Oxygen permselectivity through a base polymer membrane was highly enhanced from 1.83 to 2.36 by adding a small amount (1-5wt%) of the 2D surface modifier T-F. The improvement was thought to be caused by improvement of solution selectivity on the membrane surface which the 2D surface modifier effectively covered. Chirality 27:459-463, 2015. (c) 2015 Wiley Periodicals, Inc.

DOI： 10.1002/chir.22441

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

One-handed helical polyphenylacetylenes having achiral amino alcohol moieties, but no chiral side groups, were synthesized by the helix-sense-selective copolymerization of an achiral phenylacetylene having an amino alcohol side group with a phenylacetylene having two hydroxyl groups. Since the resulting helical copolymers were successfully utilized as chiral ligands for the enantioselective alkylation of benzaldehyde with diethylzinc, we can conclude that the main-chain chirality based on the one-handed helical conformation is useful for the chiral catalysis of an asymmetric reaction for the first time. The enantioselectivities of the reaction were controlled by the optical purities of the helical polymer ligands. In addition, the polymer ligands could be easily recovered by precipitation after the reaction. Chirality 27:454-458, 2015. (c) 2015 Wiley Periodicals, Inc.

DOI： 10.1002/chir.22455

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A one-handed helical cis-cisoidal polyphenylacetylene (P) is successfully synthesized by an asymmetric-induced polymerization of a chiral-substituted phenylacetylene having two hydroxymethyl groups. Quantitative photocyclic aromatization of P in a membrane-state followed by in situ removal of the chiral substituents affords a one-handed helical supramolecular polymer membrane of the corresponding cyclic trimer (T) with no chiral substituents. The original one-handed helicity of the precursor P is successfully transmitted to the resulting supramolecular helicity of de-T. Both the hydrogen bonds and the pi-pi stacking are thought to contribute to the retention of the chirality during the two-step reaction in the membrane state.

DOI： 10.1002/macp.201400526

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

We found that the helix-sense-selective polymerization (HSSP) of achiral phenylacetylenes having two hydroxy groups was realized by using one-handed helical poly(phenylacetylene)s as chiral cocatalysts prepared by HSSP of the same or similar achiral phenylacetylenes having two hydroxy groups. In other words, the chirality caused only by the one-handed helical backbone was found to be able to work as a cocatalyst in the chiral catalytic system. In addition, the efficiency of the chiral induction was high and almost the same as that of the HSSP by using enatiomerically pure phenylethylamine as a cocatalyst.

DOI： 10.1246/cl.141079

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Three types of homopolymerizations of p-(dimethylsilyl)-phenylacetylene (HSPA) having a terminal triple bond and a Si-H group were selectively carried out by using three kinds of polymerization catalysts. Among them poly(HSPA) synthesized by addition polymerization of its triple bond using [Rh(nbd)Cl](2) (nbd: norbornadiene)/phenylethylamine (PEA) showed a good membrane forming ability. The copolymerizations of HSPA with p-(trimethylsilyl)phenylacetylene (SPA) were carried out using [Rh(nbd)Cl](2)/PEA and the resulting copolymers were fabricated to self-supporting membranes. These membranes, including the homopolymer of HSPA, showed higher permselectivities for oxygen and carbon dioxide over nitrogen than those of poly(SPA). Incorporation of HSPA unit to poly(SPA) effectively enhanced its permselectivities with only small decrease in its permeability.

DOI： 10.1246/cl.140928

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Three novel phenylacetylenes having two hydroxyl groups via different kinds of spacers between the two hydroxyl groups and benzyl group were synthesized and polymerized. Two of the resulting polymers having oxyalkylene spacers between the hydroxyl group and benzyl group had good membrane forming ability, relatively high oxygen permselectivity and high oxygen permeability. By introducing the oxyalkylene spacers, the membrane forming abilities and oxygen permselectivity were enhanced. Oxygen permselectivity (P-O2/P-N2 = 2.67) of the polymer membrane having the longest spacers was higher than that (2.19) of polymer without any spacers. It may be because the columnar content and then defects decreased when the cis-cisoid conformation was changed to cis-transoid conformation. In addition, by decreasing the columnar content of the membrane from the polymer without any spacers, which could be controlled by conditions in membrane preparation, the membrane forming ability and oxygen permselectivity were effectively enhanced (from 2.19 to 2.61) without any drop of oxygen permeability. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2014.11.042

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS INC  

Although two-dimensional polymers (2DPs) and related materials are very attractive subjects for research because they are expected to function as ideal gas separation membrane materials, we need to answer some basic questions about them. For example, "Why are they not a common or popular topic, especially in textbooks?"; "How can they be synthesized?"; and "Whatever are 2DPs? and "How can we define 2DPs?" In this review, we try to answer these questions. First, the significance of 2DP as molecular-sieving membrane materials is explained in Section 1. Second, the definitions and classifications are proposed that take into account their first-order and high-order structures in Section 2. Third, syntheses and function of a few real 2DPs and many related polymers described in the literature are reviewed, including such materials as covalent organic frameworks(COFs), carbonized molecular sieving membranes(CMSMs), polymers of intrinsic porosity(PIM), and our recent results on the synthesis and function of 2DPs and related polymers in Sections 3 and 4. Finally, in Section 5 we evaluate the two-dimensional (2D) characters of 2DPs described in Section 3 using some 2D characteristic values defined in Section 2, and the future of 2DPs is discussed in Section 6.

DOI： 10.1080/15583724.2014.963235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Helix-sense-selective polymerisation of three new achiral substituted acetylenes containing two bulky pi-conjugated planar substituents via imino groups by using catalytic amounts of a chiral source yielded soluble and statically stable one-handed helical polymers which were stabilized by intramolecular steric hindrance.

DOI： 10.1039/c5ra20211f

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Helix-sense-selective photodegaradation of poly[4-dodecyloxy-3,5-bis(hydroxymethyl)phenylacetylene] (poly(DoDHPA)) in membrane state was achieved by selective photocyclic aromatization (SCAT) using single-handed circularly polarized light (CPL). This is the first example of kinetic optical resolution of helical polymers by using CPL.

DOI： 10.1246/cl.140469

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

5,4'-Bis(3,5-di-tert-buty1-4-acetoxypheny1)-2-ethynyl-2'-iodo-stilbene was synthesized and polymerized by the Sonogashira reaction to give the corresponding regioregular head-totail poly(1,2-phenyleneethynylene-1,2-phenylenevinylene). The polymer was converted to the corresponding hydroxy polymer after complete elimination of the protecting acetyl group by treatment with an alkaline solution. It was found that the folded helical conformation was preferred for the polymer containing the poly(1,2-phenylenevinylene) structure upon addition of methanol to the chloroform solution owing to the solvophobic interaction.

DOI： 10.1246/cl.140348

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

A facile synthesis of novel five 2D (planar) surface modifiers having a triphenylbenzene derivatives as a 2D structure has been achieved by the highly selective photocyclic aromatization reaction. Efficient enhancement of oxygen permselectivities through the three polymer membranes has been achieved by adding a small amount (< 5.0 wt%) of the 20 surface modifiers. Among the five 2D surface modifiers, a modifier compound having oligoethylene oxide groups showed the best performance for the enhancement. These improvements were thought to be caused mainly by improvement of the solution selectivity on the membrane surface where the 2D surface modifiers were accumulated. In some of the surface-modified blend membranes, their plots in the P-O2(-alpha) graph were over or close to the upper boundary line by Robeson in 1991. Since all the membranes containing the 2D surface modifiers showed better permselectivities than the corresponding substrate membranes, it is very promising for the future. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2013.11.046

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Some 1,3-PPE-based polyradicals with pendent phenoxy radicals whose repeating unit consisted of four 1,3-phenyleneethynylene units were synthesized via polymerization between monomers and trimeric monomers in the presence of the Pd(PPh3)(4) complex catalysts. The ESR spectra of the polyradicals in dichloromethane showed unimodal broad signals. For the solid samples which were prepared from the dichloromethane solution by evaporating the solvent and by drying in vacuo, the signal intensity decreased with broadening of peak-to-peak line-width (Delta H-pp). However, the ESR spectra almost recover to the initial intensity and shapes due to redissolving in dichloromethane. In particular, the decrease of doubly integrating the ESR signal (I-ESR) was more remarkable for the polyradical bearing galvinoxyl and phenoxyl residues than others. This behavior suggests that strong antiferromagnetic interaction partially arose for the polyradical. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2014.01.019

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

An insoluble chiral membrane of one-handed helical multihydroxy poly(phenylacetylene) without the coexistence of any other chiral moieties has been synthesized by in situ complete removal of a one-handed helical poly(phenylacetylene) having multihydroxymethyl groups and chiral pinanyl groups in each polymeric unit in the membrane state. Although the enantiopermselectivity was decreased, the permeability increased four times by removing the chiral groups. In comparison with the corresponding poly(phenylacetylene) having no hydroxymethyl groups and chiral pinanyl groups, the loss of enantiopermselectivity was much lower. It is believed that the multihydroxy groups could maintain the main-chain chirality or enhanced interaction with permeant.

DOI： 10.1246/cl.130896

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Society of Polymer Science  

Novel substituted acetylenes having a rigid planar substituent via a dynamic covalent imino group were synthesized and subsequently polymerized by using a chiral initiator system consisting of an achiral rhodium complex and a chiral N,N-dimethylphenylethylamine to produce one-handed helical polymers having dynamic covalent imino groups. Furthermore, membranes could be produced from these chiral polymers that showed highly selective photocyclic aromatization (SCAT) and quantitative substitution of the side groups (RIM). Supramolecular polymer membranes having a high strength were obtained by SCAT. Chiral polymer membranes having many different kinds of side groups were easily obtained by RIM of the side groups. © 2014, The Society of Polymer Science.

DOI： 10.1295/koron.71.372

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：SOC POLYMER SCIENCE JAPAN  

Novel substituted acetylenes having a rigid planar substituent via a dynamic covalent imino group were synthesized and subsequently polymerized by using a chiral initiator system consisting Of an achiral rhodium complex and a chiral N,N-dimethylphenylethylamine to produce one-handed helical polymers having dynamic covalent imino groups. Furthermore, membranes could be produced from these chiral polymers that showed highly selective photocyclic aromatization (SCAT) and quantitative substitution of the side groups (RIM). Supramolecular polymer membranes having a high strength were obtained by SCAT. Chiral polymer membranes having many different kinds of side groups were easily obtained by RIM of the side groups.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

An achiral 3,5-bis(hydroxymethyl)phenylacetylene connected with a rigid and pi-conjugated substituent was polymerized using a rhodium (Rh) complex catalyst in the presence of chiral 1-phenylethylamines. The circular dichroism (CD) spectra of the polymers indicated that an excess of one-handed helical polyacetylene backbone was induced by helix-sense-selective polymerization under the asymmetric conditions despite the achiral monomer. The split-type-induced CD signals at 300 nm were attributed to the chromophore including the conjugated side group since the signal appeared at a longer wavelength than the poly[3,5-bis(hydroxymethyl)phenylacetylene] without conjugated substituent.

DOI： 10.1246/cl.130339

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

An amphiphilic 1,3,5-trisubstituted benzene as a new 2D surface modifier (T-EO) which has six hydroxy groups and three oligoethylene groups was successfully and easily synthesized by selective photocyclic aromatization in high conversion and selectivity for the first time. We prepared four kinds of blend membranes based on PVA or poly(trimethylsilylphenylacetylene) (poly(SPA)) containing the new amphiphilic cyclic trimer (T-EO) or the corresponding polymer (P-EO), that is, T-EO/PVA, P-EO/PVA, and T-EO/poly(SPA) membranes prepared by conventional solvent casting method (Method 1) and T-EO/poly(SPA) membranes prepared by a new solvent casting method (Method 11). T-EO/PVA membranes by Method I and T-EO/poly(SPA) membranes by Method II showed better performance in oxygen permeation than P-EO/PVA membranes by Method I and T-EO/poly(SPA) membranes by Method I, respectively. A PVA-based membrane containing 1.0 wt % T-EO showed the best performance, that is, the alpha became twice that of the original PVA membrane without any decrease in P-O2. The ideal improvement may be caused by effective surface modification by T-EO.

DOI： 10.1246/cl.130372

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Language：English   Publishing type：Research paper (scientific journal)  

It has been achieved to obtain flexible self-supporting supramolecular polymeric membranes consisting of only 1,3,5-trisubstituted benzene derivatives prepared by highly selective photocyclic aromatization of the corresponding poly (substituted phenylacetylene)s having a columnar structure. The flexibilities of the self-supporting supramolecular polymeric membranes were enhanced by introducing hydroxyl groups or phenylene groups to the starting polymers (monomers). There were two reasons for the enhanced strength: 1) introduction of intercolumnar hydrogen bonds and 2) enhancement of the degree of intracolumnar stackings. This strength depended on the structure of the starting polymers which functioned as a template. © 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2013.05.063

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A novel phenylacetylene (1) having two hydroxyl groups and a chiral pinanyl group together with the other three related phenylacetylenes has been synthesized and (co)polymerized by using an achiral catalytic system. Among the four monomers, only 1 is suitable to the asymmetric-induced polymerization (AIP). Chiral amplification phenomenon is only observed in the copolymerization of 1 with an achiral phenylacetylene having two hydroxyl groups (3). The tight helical cis-cisoidal main chain formed by making intramolecular hydrogen bonds between the hydroxyl groups in the copoly(1/3) enhances the efficiency of chiral induction and as a result chiral amplification phenomenon is observed during the copolymerization.

DOI： 10.1002/marc.201300318

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Two poly(trimethylsilyldiphenylacetylene) membranes containing different contents of fluorine-containing groups were prepared by direct perfluorodecylation of poly(trimethylsilyldiphenylacetylene) (poly 1) in the membrane state using different ratios of (perfluorodecyl)phenyliodonium triflates to the phenyl groups in the polymer. The resulting perfluorodecylated poly(trimethylsilyldiphenylacetylene) (poly 2a and poly 2b) membranes were self-standing and tough. The two membranes showed better performance in oxygen permselectivity compared with all the membranes reported by many researchers. The performance (PO2 &gt
103 barrer and α = PO 2/PN2 = 2.9) of the poly 2a membrane having a lower content of the fluorine groups located on the upper boundary line reported by Robeson in 2008. The poly 2b membrane having a higher content of the fluorine groups was one of the polymers having the highest PO2 values (PO 2 &gt
104 barrer) in all the polymers reported.

DOI： 10.1016/j.polymer.2013.03.008

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

We synthesized poly(1,3-phenyleneethynylene)s bearing galvinoxyl moieties. The absorption ratio of the anion form in 1 M KOH methanol solution between 309 and 294 nm (A(309)/A(294)) decreased with increasing degree of polymerization. The wide-angle X-ray scattering of the powder, which was prepared by precipitation in dilute hydrochloric acid solution from the anion form in 1 M KOH methanol solution, showed a crystalline peak at 2 theta = 28 degrees. Polymers in which the chiral diethynyl-1,1'-binaphthyl moiety was inserted into the poly(1,3-phenyleneethynylene) chain were synthesized, and clear Cotton effects were observed in the absorption region of the galvinoxyl anion chromophore in the CD spectra taken in 1 M KOH-MeOH solution, indicating an excess of one-handed folded helical conformation. A relatively strong antiferromagnetic interaction was observed for the polyradicals prepared by precipitating the anionic form from alkaline methanol solution accompanied with oxidation using aqueous K3Fe(CN)(6) solution. These observations suggest that the relatively strong antiferromagnetic interaction of the polyradicals was caused by the close packing between galvinoxyl radicals induced by the formation of the folded helical structure.

DOI： 10.1021/ma302314n

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

By using a new achiral phenylacetylene having bulky substituents as a monomer, living-like helix-sense-selective polymerization (HSSP) has been achieved. This is the first example of the HSSP of substituted acetylenes where the degree of polymerization was controlled. The resulting one-handed helical living polymer initiated polymerization of a second monomer to successfully yield a block copolymer. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2013.02.009

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Zwitterionic rhodium (Rh) complexes with tethered chiral amino and ether groups were synthesized by the reaction of [(C2H4)(2)RhCl](2) with the 2,5-norbornadiene tether, (CH2)(4)R [2: R = (R)-NHCH(CH3)Ph, 3: (R)-OCH(CH3)Ph], followed by exchange of Cl with BPh4. The resultant Rh complexes, 2 and 3, catalyzed the polymerization of 4-dodecyloxy-3,5-bis(hydroxymethyl)phenylacetylene (1) to afford polymers [poly(1)s] with number-average molecular weights of 16000 and 82000, respectively. The poly(1)s showed clear circular dichroism resulting from their polyacetylene backbones, which indicates the formation of predominantly one-handed helical structures.

DOI： 10.1246/cl.2013.278

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A novel, highly selective photocyclic aromatization (SCAT) of π-conjugated polymers from phenylacetylene having two hydroxyl groups to exclusively yield a 1,3,5-trisubstituted benzene derivative was developed, and its success was confirmed by 1H NMR, GPC, and TOF-MS. The SCAT reaction has many unique characteristics. (1) It is a quantitative reaction: it gave only the corresponding cyclic trimer, i.e., a 1,3,5-trisubstituted benzene derivative, quantitatively (100%). No byproducts were produced under the best conditions. (2) It is an intramolecular reaction: it occurred between three adjacent monomer units in one macromolecule. (3) It is a stereospecific and topochemical or template reaction: the reactivity strongly depended on the configuration and conformation of the starting polymer substrates. (4) It is a photoreaction: high selectivity (100%) was observed only by the use of visible light irradiation, not by heating. (5) It is a solid-state reaction: high selectivity (100%) was observed only in the solid state, not in solution. In addition, (6) the resulting cyclic trimers could form a self-supporting membrane, despite their low molecular weights. This new approach resulted in a new class of supramolecular polymers consisting of a 1,3,5-trisubstituted benzene derivative, numbers of which were linearly linked by hydrogen bonds and stacked benzene derivatives. Since SCAT has such high selectivities and is useful for the preparation of a self-supporting supramolecular polymer membrane, many applications can be expected. © 2012 American Chemical Society.

DOI： 10.1021/ja3113214

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Language：English   Publishing type：Research paper (scientific journal)  

Helix-sense-selective polymerization (HSSP) of substituted acetylenes by using an isolated chiral Rh initiator with an amino acid ligand has been achieved. The sense of the helix of the main chain of the resulting polymer was controlled by the sign of the chirality of the ligand. The isolated initiator needed less of the chiral ligand and gave polymers having a higher value than the two component chiral initiator systems we reported previously. The resulting polymers had a higher Mw. © 2013 The Chemical Society of Japan.

DOI： 10.1246/cl.121295

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Four novel chiral phenylacetylenes having an L-amino alcohol residue and two hydroxymethyl groups were synthesized and polymerized by an achiral catalyst ((nbd)Rh+[?6-(C6H5)B-(C6H5)3]) or a chiral catalytic system ([Rh(nbd)Cl]2/(S)- or (R)-phenylethylamine ((S)- or (R)-PEA)). The two resulting polymers having an L-valinol or L-phenylalaninol residue showed Cotton effects at wavelengths around 430 nm. This observation indicated that they had an excess of one-handed helical backbones. Positive and negative Cotton effects were observed only for the polymers having an L-valinol residue produced by using (R)- and (S)-PEA as a cocatalyst, respectively, although the monomer had the same chirality. Even when the achiral catalyst was used, the two resulting polymers having an L-valinol or L-phenylalaninol residue showed Cotton effects despite the long distance between the chiral groups and the main chain. We have found the first example of a new type of chiral monomer, that is, a chiral phenylacetylene monomer having an L-amino alcohol residue and two hydroxy groups that was suitable for both modes of asymmetric polymerization, that is, the helix-sense-selective polymerization (HSSP) with the chiral catalytic system and the asymmetric-induced polymerization (AIP) with the achiral catalyst. The other two monomers having L-alaninol and L-tyrosinol were found to be unsuitable to neither HSSP nor AIP because of their polymers' low solubility. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

DOI： 10.1002/pola.26346

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

In this study, we investigated the helix-sense-selective polymerizations of newly synthesized achiral phenylacetylenes having two N-alkylamide groups, such as 3,5-bis(dodecylamide)phenylacetylene (DAPA), 3,5-bis(octylamide)phenylacetylene (OAPA), and 3,5-bis(butylamide)phenylacetylene (BAPA), by using a chiral rhodium catalyst system ([Rh(nbd)Cl](2)-(R)-(+)-1-phenylethylamine [(R)-PEA]). Poly(BAPA) was insoluble in any solvents. On the other hand, poly(DAPA) and poly(OAPA) were soluble in toluene, THF, and CHCl3, and the obtained polymers showed intense circular dichroism signals at the absorption region of the main chain in the UVvis region. This result suggested those polymers were present in helical conformations with an excess of one-handed screw sense. The chiral helix structures of the formed polymers were stable in toluene at room temperature for a long time because of intramolecular hydrogen bonds. This result is the second example about polyacetylenes with one-handed helical conformation stabilized by intramolecular hydrogen bonds.

DOI： 10.1021/mz300309c

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Copoly(hyperbranched macromonomer)s, i.e., poly(phenylacetylene)s having many branches were synthesized by one-pot simultaneous copolymerization of two kinds of dimethylsilyl-phenylacetylenes. Membranes from the copoly(hyperbranched macromonomer)s having several kinds of branches showed higher permselectivities for oxygen and carbon dioxide over nitrogen than those of the corresponding copoly(hyperbranched macromonomer)s without any branches. In particular, the copoly(hyperbranched macromonomer)s having long and rigid branches had both the advantages of poly(phenylacetylene)s and poly(dendron)s. In summary, copoly(hyperbranched macromonomer)s showing good performance as gas-separation membranes were synthesized very easily by the one-pot simultaneous polymerization method. To our knowledge, this is the first synthesis of such complex copolymers showing good performance as gas-separation membranes.

DOI： 10.1246/cl.2012.1462

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

A soluble and stable one-handed helical conjugated polymer without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer having two hydroxyl groups followed by desubstitution of the chiral groups in a solid membrane state. The reason for the success was the polymer reaction was carried out in the membrane state. This is an alternative method to obtain such a unique chiral polymer which was obtained only by the helix-sense-selective polymerization (HSSP) we reported before. In addition the efficiency of the chiral induction was higher than that of the HSSP. It is interesting that the "Membrane state" acted like as if a protecting group. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2012.03.022

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Homochiral or enantioenriched helical polymers are essential for investigating the relationship between chirality of helical structures and their performance in the design of various optically active functional polymers. We have succeeded in obtaining the helical poly(phenylacetylene)s poly(1)-poly(6) possessing no chiral moieties, except for helicity; the enantioenriched helical sense of these polymers was induced by transformation in chiral solvents, followed by removal of the chiral solvents, even if the interaction between the chiral molecule and the polymer was weak such as solvent-solute interaction. In particular, the newly synthesized poly(6) retained the induced helical sense even in an achiral solvent. Polymer Journal (2012) 44, 327-333; doi:10.1038/pj.2011.144; published online 18 January 2012

DOI： 10.1038/pj.2011.144

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Language：English   Publisher：AMER CHEMICAL SOC  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A new polymer prepared by polymerization of 3,5-bis(hydroxymethyl)phenylacetylene having a chiral menthyl group via a very long and rigid spacer by an achiral rhodium complex with triethylamine as an initiator showed strong CD absorptions assigned to the main chain in spite of the long distance (23 angstrom) between the chiral group and the polymerizing group in the monomer. This distance is the longest to the best of our knowledge. In addition, switching between the two chiralities of the resulting polymer was realized in the CD spectrum.

DOI： 10.1246/cl.2012.244

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

A soluble and stable one-handed helical poly(substituted phenylacetylene) without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer followed by two-step polymer reactions in membrane state: (1) removing the chiral groups (desubstitution); and (2) introduction of achiral long alkyl groups at the same position as the desubstitution to enhance the solubility of the resulting one-handed helical polymer (resubstitution). The starting chiral monomer should have four characteristic substituents: (i) a chiral group bonded to an easily hydrolyzed spacer group; (ii) two hydroxyl groups; (iii) a long rigid hydrophobic spacer between the chiral group and the polymerizing group; (iv) a long achiral group near the chiral group. As spacer group a carbonate ester was selected. The two hydroxyl groups formed intramolecular hydrogen bonds stabilizing a one-handed helical structure in solution before and after the two-step polymer reactions in membrane state. The rigid long hydrophobic spacer, a phenylethynylphenyl group, enhanced the solubility of the starting polymer, and realized effective chiral induction from the chiral side groups to the main chain in the asymmetric-induced polymerization. The long alkyl group near the chiral group avoided shrinkage of the membrane and kept the reactivity of resubstitution in membrane state after removing the chiral groups. The g value (g = ([theta]/3,300)/epsilon) for the CD signal assigned to the main chain in the obtained final polymer was almost the same as that of the starting polymer in spite of the absence of any other chiral moieties. Moreover, since the one-handed helical structure was maintained by the intramolecular hydrogen bonds in a solution, direct observation of the one-handed helicity of the final homopolymer has been realized in CD for the solution for the first time.

DOI： 10.3390/molecules17010433

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：HINDAWI PUBLISHING CORPORATION  

Monodendron monomers with alkoxy peripheral groups were synthesized, and the focal point of monodendrons, terminal acetylene, was polymerized with rhodium catalyst to yield corresponding polydendrons with a high molecular weight. The polydendrons were soluble in common organic solvents and readily formed membranes. Oxygen permselectivity was improved in the polydendrons with a space-persistent dendritic crowd. It was found that the well-defined dendritic and rod-like structure of the polydendrons was useful for permselective membrane.

DOI： 10.1155/2012/974204

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Pseudo helix-sense-selective polymerisation of a wide range of achiral substituted acetylenes having dynamic covalent bonds has been realised to yield static one-handed helical polymers without any other chiral moieties.

DOI： 10.1039/c2cc00030j

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Language：English   Publishing type：Part of collection (book)   Publisher：John Wiley and Sons  

DOI： 10.1002/9781118063965.ch15

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

We synthesized two kinds of poly(1,3-phenyleneethynylenes), one has (+)-menthoxycarbonyl groups at all repeating units and the other has (+)-menthoxycarbonyl groups and n-dodecyloxy groups alternately. Self-supporting membranes could be obtained easily by solvent casting. Enantioselective permeations of the polymers were investigated by pervaporation of 2-butanol. Enantioselective permeabilities of the membrane consisting of one-handed helical foldamer and unfoldamer were clarified.

DOI： 10.1246/cl.2011.384

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Engineering Education  

An educational practice entitled "Breaking Away from Shallow Learning Habits" of the Faculty of Engineering, Niigata University is adopted as "Good Practice (GP) of Education" by The Ministry of Education, Culture, Sports, Science and Technology. This practice consists of a new introductory educational program for freshmen entitled "Introduction to Engineering Literacy" , as well as improvement of other lectures/experimentations/exercises for design education. "Introduction to Engineering Literacy" of The Department of Chemistry and Chemical Engineering, is programmed to let the students make "failure" (discrepancy from the knowledge obtained from the textbooks) in experiments, let them propose improvement, and let them conduct the same experiment again after the improvement, so that the freshmen can experience a PDCA (Plan-Do-Check-Action) cycle.

DOI： 10.4307/jsee.59.2_74

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

To develop new phenylacetylene monomers more suitable for helix-sense selective polymerization (HSSP) we reported previously and to improve the efficiency of the HSSP and membrane performance of the resulting polymers, novel phenylacetylenes having a flexible oligosiloxanyl group (SnBDHPA) together with the other related three series of monomers were synthesized and polymerized by using a chiral catalytic system and enantioselectivity in permeation of the membranes from the resulting chiral polymers were examined SnBDHPA was the most suitable for the HSSP and the CD absorptions (G values) of poly (SnBDHPA) were stronger and more stable than those of the corresponding polymers having rigid alkyl groups The polymers could be fabricated to flexible self supporting membranes by using solvent casting method In addition, enantioselectivity in permeation of one of poly(SnBDHPA) membranes was much higher than that of a poly(phenylacetylene) membrane having alkyl groups This was because the polymers having oligosiloxane groups had high regularity of structures, i e, chemical structures of the macromolecules such as one handedness and high order structures such as columnar contents in the membranes, and the membranes were flexible and had almost no defects These good properties as optical resolution membrane materials were caused by flexibility, hydrophobicity, and bulkiness of the oligosiloxane chains S3BDHPA having a trisiloxanyl group was found to be the best monomer for the HSSP and for obtaining good optical resolution membrane materials

DOI： 10.1021/ma101999k

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Three novel chiral phenylacetylenes having in octyloxyethanolamine residue derived from a L-aminoalcohol and two hydroxymethyl groups were synthesized and polymerized by two achiral catalysts ((nbd)Rh(+)[eta(6)-(C(6)H(5))B(-)(C(6)H(5))(3)] and [Rh(nbd)Cl](2)/triethylamine (TEA)) and a chiral catalytic system ([Rh(nbc)Cl](2)/(S)- or (R)-phenylethylamine ((S)- or (R())-PEA)). All of the resulting polymers showed Cotton effects at wavelengths around 430 nm. This observation indicated that they had an excess of one-handed helical backbones. Positive and negative Cotton effects were observed for the polymers having an L-valinol residue produced by using (S)- and (R)-PEA as it cocatalyst, respectively, although the monomers had the same chirality. The two polymers having in L-aliminol or L-phenylalaninol residues obtained by using (S)- and (R)-PEA as a cocatalyst showed CD absorptions with identical signs. Therefore, we found that the chiral monomer having an L-valinol residue was suitable for both modes of asymmetric polymerization, that is, helix-sense-selective polymerization (HSSP) with the chiral catalytic system and asymmetric-induced polymerization (AIP) with the achiral catalysts. However, the other two monomers having an L-alaninol or L-phenylalaninol residue were not suitable for HSSP because the helix sense could not be controlled by the chirality of PEA. To explain the unexpected behaviors in the asymmetric polymerizations of the two chiral monomers having a chiral bidentate ligand, a novel third mechanism of asymmetric polymerization, that is, self-helix-sense-selective polymerization (SHSSP), is proposed in this Article. This Article discusses the contribution of the three mechanisms (AIP, HSSP, and SHSSP) in asymmetric polymerizations of the three monomers.

DOI： 10.1021/ma101424x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

To develop a new phenylacetylene monomer suitable for helix-sense-selective polymerization (HSSP) we reported previously and to improve the efficiency of the HSSP and membrane performance of the resulting polymer, a novel phenylacetylene having a trisiloxanyl group (S3BDHPA) was synthesized and polymerized by using a chiral catalytic system and enantioselectivity in permeation of its membrane was examined. S3BDHPA was suitable for the HSSP and the CD absorption of poly(S3BDHPA) was stronger and more stable than that of the corresponding polymer having no siloxanyl groups. In addition, enantioselectivity in permeation of poly(S3BDHPA) was much higher than that of a polymer membrane having no siloxanyl groups. They are thought to be caused by the flexibility and hydrophobicity of the trisiloxane groups. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2010.04.030

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We synthesized optically active polyradicals possessing an excess of one-handed helical backbone by helix-sense-selective polymerization (HSSP) of achiral monomers which was promoted by rhodium complex catalyst in the presence of (R)- or (S)-1-phenylethylamine. The monomer, which had two hydroxy groups and a hydrogalvinoxyl unit, gave the corresponding polymer with an optically active helical conformation stabilized by intramolecular hydrogen bonding. The chemical oxidation of the polymer yielded the corresponding optically active helical polyradical with high spin concentration. The static magnetic susceptibility of the chiral polyradical was measured using a SQUID magnetometer. We have found that the stronger antiferromagnetic interaction was observed for the polyradical synthesized by HSSP in comparison with the polyradical via polymerization in the presence of racemic phenylethylamine. (C) 2008 Elsevier Ltd. All rights reserved

DOI： 10.1016/j.poly.2008.10.067

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

In this study, we synthesized four chiral helical poly(phenyleneethynylenes) having optically active menthoxycarbonyl groups and desubstituted the chiral groups in membrane state. Polycondensations of (+)-menthyl 3,5-diethynylbenzoate with (+)-menthyl 3,5-diiodobenzoate, 1,2-diiodobenzenen, 1,3-diiodobenzene, and 1,4-diiodobenzene using PdCl(2)(PPh(3))(2)-PPh(3)-Cul were afforded helical polymers in good yields (named as PMtMt, o-PMtH, m-PMtH, and p-PMtH, respectively). Among them, PMtMt in a mixture of chloroform/benzene showed the largest Cotton effect in absorption region and gave self-supporting membrane by solvent-casting method. PMtMt membrane also showed a Cotton signal similar to that observed in solution. Desubstitution of PMtMt proceeded quantitatively by immersing the membrane into alkaline solution at room temperature for 3 days. The desubstituted PMtMt membrane showed circular dichroism (CD) signals similar shape to that of the original membrane in the UV region in despite of the polymer having no chiral moieties except for helical conformation. This is the first example of synthesis of chiral helical poly(phenyleneethynylenes) without the coexistence of any other chiral moieties. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.synthmet.2009.01.038

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

We synthesized an optically active poly(binaphthyl-6,6'-diylethynylene-1,3-phenyleneethynylene) with pendant galvinoxyl residues. The hydrogalvinoxyl precursor polymer was given by polymerization of (1,3-diiodophenyl)hydrogalvinoxyl and 6,6'-diethynyl-2,2'-dihexyloxybinaphthyl using Pd(PPh(3))(4) catalyst (M(w) = 4.6 x 10(4), M(w)/M(n) = 30). The polymer yielded the corresponding polyradical with high spin concentration by treatment of the polymer solution with PbO(2). In the CD spectra of the polymer and polyradical taken in various solutions, clear Cotton effects were observed in the absorption region of the binaphthyl chromophore, while no Cotton effect was observed in that of the galvinoxyl chromophore. On the other hand, in the MCD, Faraday effects were observed in the absorption region of the backbone and galvinoxyl chromophore. The static magnetic susceptibility of the chiral polyradical was measured using a SQUID magnetometer, and showed weak antiferromagnetic interaction. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.synthmet.2009.01.042

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

4-Alkyloxy-3,5-bis(hydroxymethyl)phenylacetylenes with eight types of alkyl groups were synthesized and polymerized with a chiral catalytic system. We found that the length of the alkyl groups played a very important role in achieving helix-sense-selective polymerization. Five helix-sense-selective polymerizations were achieved resulting in polymers with alkyl groups whose chain length was longer than six. We think that the longer-chain alkyl groups prevented the polymers from becoming insoluble by forming intermolecular hydrogen bonds between the hydroxyl groups, and stabilized their one-handed helical structure by promoting the formation of intramolecular hydrogen bonds.

DOI： 10.1002/macp.200800594

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/ma802313z

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Phenyleneethynylene macrocycle-substituted acetylenes were synthesized by repetition of the Sonogashira coupling reaction, and the elimination reaction of the terminal acetylene protecting group. The monomers were polymerized with a rhodium catalyst, [Rh(nbd)Cl](2), at the terminal acetylene unit, and the polymerization mixtures were purified by precipitating into methanol to yield the corresponding poly(phenylacetylene) derivatives as yellow-red powders, which had a high degree of polymerization ((DP) over bar approximate to 500) in spite of their steric bulkiness. The trimethylsilyl and pentamethyldisiloxanyl groups of polymers improved their solubility, and the polymers were soluble in common organic solvents, such as toluene, chloroform and tetrahydrofuran.

DOI： 10.1002/macp.200800429

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Achiral phenylacetylene monomers were polymerized using a rhodium (Rh) complex catalyst in the presence of (S)1-phenylethylamine. Addition of copper(I) iodide (CuI) into the catalytic system improved the polymer yield. The monomer, which had two hydroxy groups and a hydrogalvinoxyl unit, gave the corresponding polymer with an optically active helical conformation stabilized by intramolecular hydrogen bonding. The chemical oxidation of the polymer yielded the corresponding optically active helical polyradical with high spin concentration.

DOI： 10.1246/cl.2008.390

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Helix-sense-selective polymerization of {4-[(3,5-di-tert-butyl-4-hydroxyphenyl)(3,5-di-tert-butyl-4-oxo-cyclohexa-2,5-dienylidene)methyl]phenyl}acetylene (abbreviated as (4-ethynylphenyl)hydrogalvinoxyl) was promoted by [Rh(cod)Cl](2) and [Rh(nbd)Cl](2) catalyst in the presence of (R)-(+)-1-phenylethylamine or (S)-(-)-1-phenylethylamine (PEA). The [Rh(cod)C](2) Catalyst system gave red polymers whose CD spectra showed the stronger Cotton effect though the yield (2-3%) and molecular weight (M-n = (1.1 - 1.4) x 10(4)) were lower than those of polymers obtained by [Rh(nbd)Cl](2). Moreover, we investigated the effect of bulkiness of the catalyst, cocatalyst, and monomer on helix-sense-selective polymerization of (4-ethynylphenyl)hydrogalvinoxyl in the presence of (R)-PEA. The CD patterns of polymers obtained by [Rh(nbd)Cl](2) and [Rh(cod)Cl](2) were nearly mirror image of each other, except for the magnitudes of the signals in spite of the same chiral condition, i.e., in the presence of (R)-PEA. That is, [Rh(nbd)Cl](2) and [Rh(cod)Cl](2) catalysts generated P-helix and M-helix, respectively. This is a novel result, since the control of helix sense is usually achieved by enantiomeric moieties of catalysts or initiators for the helix-sense-selective polymerization.

DOI： 10.1021/ma0713963

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A nanocomposite film of tungsten trioxide (WO3) and [Ru(bpy)(3)](2+) (bpy = 2,2'-bipyridine) (denoted as Ru-WO3) was prepared from an aqueous colloidal triad solution containing peroxotungstic acid, [Ru(bpy)(3)](2+), and poly(sodium 4-styrenesulfonate) by an electrodeposition technique. The electrochemical features of the Ru-WO3 film were investigated using cyclic voltammetry (CV) and potential-step chronoamperospectrometry (PSCAS) techniques, compared with those in a [Ru(bpy)(3)](2+)/Nafion (Ru-Nf) film. PSCAS data spectrophotometrically showed that Ru-II is completely oxidized for 0.3 s in the Ru-WO3 film, in contrast to the corresponding reaction completed for 30 s in the Ru-Nf film. The apparent diffusion coefficient (D-app = (0.1-1.1) x 10(-7) cm(2) s(-1)) for charge transport (CT) by a Ru-II/Ru-III redox in the Ru-WO3 film was higher than that (2.4 x 10(-10) cm(2) s(-1)) in the Ru-Nf film by 2 or 3 orders of magnitude. Activation energy (E-a) for CT (14.1 kJ mol(-1)) for the Ru-WO3 film was 3.5 times lower than that (E-a = 49.8 kJ mol(-1)) for the Ru-Nf film. The lower E-a could be responsible for the faster CT in the Ru-WO3 film than the Ru-Nf film. D-app in the Ru-WO3 film increased linearly with an increase of the final applied potential (E-f) for PSCAS from 1.2 to 1.5 V vs SCE and saturated above E-f = 1.5 V. The mechanism for CT in the Ru-WO3 film is proposed, in which electrons are injected from [Ru(bpy)(3)](2+) into the conduction band (CB) of WO3 and go through there to a collector electrode.

DOI： 10.1021/jp073020x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A hybrid film of WO3/tris(2,2'-bipyridine)ruthenium(II) ([Ru(bpy)(3])(2+)) /poly(sodium 4-styrenesulfonote) (PSS) (denoted as a WRP hybrid film) was prepared as a base layer on an indium tin oxide electrode substrate by cathodic electrodeposition from a colloidal ternary solution containing peroxotungstic acid, [Ru(bpy)(3)](2+), and PSS. Prussian blue, Fe-4(III)[Fe-II(CN)(6)](3) (Fe-II-Fe-III) was cathodically electrodeposited on the WRP hybrid film from a Berlin brown (Fe-II-Fe-III) colloidal solution to give a WRP/Fe-II-Fe-III biloyer film. Spectrocyclic voltammetry measurement of the WRP/ Fe-II-Fe-III bilayer film reveals that Prussian white (Fe-II-Fe-III) is oxidized to Fe-II-Fe-III by electrogenerated Ru-III, and Fe-II-Fe-III is re-reduced to Fe-II-Fe-III by electrogenerated HxWO3. Visible-light irradiation of the WRP hybrid film generates a small photocurrent (approximate to 8 nA cm(-2)) at 0.4 V of an applied potential, whereas irradiation of the WRP/Fe-II-Fe-III bilayer film (Fe-II-Fe-III is electrochemically reduced to the Fe-II-Fe-III state) significantly generates a steady photoonodic current of 2.0-1.1 mu A cm(-2) under the some conditions, thus demonstrating that the photoanodic current is produced by the layered Fe-II-Fe-III film. The photoaction spectrum of the bilayer film reveals that the photoanodic current is based on the photoexcitation of [Ru(bpy)(3)](2+). The photogeneration of Fe-II-Fe-III from Fe-II-Fe-III is shown by the absorption spectral change of the bilayer film on irradiation. These results corroborate the notion that Fe-II-Fe-III is oxidized by photogenerated Ru-III to generate Fe-II-Fe-III. However, the rote of photogenerotion of Fe-II-Fe-III is slow, which could be ascribed to the fast back electron transfer (ET) from WO3 to Ru-III, comparable with the forward ET from Fe-II-Fe-III to Ru-III. The fast back ET could be a crucial problem for the [Ru(bpy)(3)](2+)-sensitized reaction in the hybrid film.

DOI： 10.1002/cphc.200700192

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We synthesized an optically active helical poly(1,3-phenyleneethynylene) with pendant galvinoxyl residues and dimethyl(10-(1S)pinanyl)silyl groups. The hydrogalvinoxyl precursor polymer was given by polymerization of (1,3-diiodophenyl)hydrogalvinoxyl and 1,3-diethynyl-5-[dimethyl(10-(1S)-pinanyl)silyl]benzene using Pd(PPh3)(4) catalyst (M-w = 1.7 x 10(5), M-w/M-n = 3.7). In the CD spectrum taken in ethyl acetate solution, clear Cotton effects were observed in the absorption region of the backbone and hydrogalvinoxyl chromophore, indicating an excess of one-handed helical foldamer conformation. The polymer yielded the corresponding polyradical with high spin concentration by treatment of the polymer solution with PbO2. The Cotton effects appeared in CD spectra of the polymer and polyradical by addition of methanol to the chloroform solution, although the Cotton effects were hardly observed in chloroform. On the other hand, in the MCD spectra of the polymer and polyradical taken in chloroform solution, Faraday effects were observed in the absorption region of the backbone and galvinoxyl chromophore. The static magnetic susceptibility of the chiral polyradical was measured using a SQUID magnetometer, and showed the antiferromagnetic interaction. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.poly.2006.09.104

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A chiral helical poly(phenylacetylene) bearing N-(2-hydoroxyethyl)aminomethyl groups as ligand sites was synthesized by helix-sense-selective polymerization. In the obtained polymeric membrane, the ligands could complex with Cu2+. In permeation of aqueous solution of racemic phenylalanine, enantioselectivity in permeation through the Cu2+ complexing membrane was about 3 times higher than that of the original membrane.

DOI： 10.1246/cl.2007.220

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Monodendrons consisting of m-linked phenyleneethynylene repeating unit with trimethylsilyl-, pentamethyldisiloxanyl- and nonamethyltetrasiloxanyl-peripheral groups were synthesized using the convergent approach. The focal point of monodendrons, terminal acetylene, was polymerized with rhodium catalyst to yield corresponding polydendrons with a high molecular weight. The polydendrons were solubile in common organic solvents, and readily formed membranes. Oxygen permselectivity was improved in the polydendrons with a space-persistent dendritic crowd. It was found that the well-defined dendritic and rod-like structure of the polydendrons was useful for pemselective membrane. Oxygen permselectivity was increased in polydendrons with a trimethylsilyl group compared to the corresponding zero generation poly(phenylacetylene) derivatives. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.memsci.2005.11.023

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

We synthesized poly(1,3-phenyleneethynylene) derivatives bearing galvinoxyl groups. The chiral polymer was synthesized by polycondensation of (1,3-diiodophenyl)hydlogalvinoxyl and chiral diethynylbenzene monomers using Pd-catalyst (yield = 87%, M n, = 4.7×10 4, M w / M n= 4.1). The CD spectrum of the poly(1,3- phenyleneethynylene) bearing hydrogalvinoxyl and chiral pinanylsilyl groups showed the Cotton effect in chloroform/methanol (1/1 v/v) at -10 °C. The chiral polyradical was obtained by chemical oxidation of the corresponding hydroxyl polymer, which was confirmed by the Cotton effect of galvinoxyl radical chromophore at 470nm. The magnetic properties of polyladicals were discussed using ESR, CD and a SQUID magnetometer.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

Chiral helical poly(phenylacetylene) bearing ligand site was synthesized by helix-sense-selective copolymerization of DoDHPA and HAMPA. Solubility and CD activity of the obtained copolymer decreased with the increase of HAMPA content. The copolymer membrane exhibited complexation ability with Cu2-. In permeation tests of aqueous solution of racemate of DL-phenylalanine, the Cu2- coordinated copolymer membrane showed enantioselective permeability higher than original copolymer membrane. This suggests that the complexation may improve chiral recognition ability of the polymer.

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We synthesized chiral/achiral phenylacetylenes with or without two hydroxyl groups (1-4). CD active polymers were obtained by polymerization of optically active pinanylsilyl group and two hydroxyl groups containing monomer (1) using achiral Rh catalyst and dodecyl group and two hydroxyl groups containing monomer (3) using chiral Rh catalyst. On the other hand, polymerizations of monomers without two hydroxyl groups having optically active pinanylsilyl group (2) or dodecyl group (4) using achiral Rh catalyst gave CD inactive polymers. The obtained polymers showed the lower angle side peaks around 2θ = 4.0-5.0° (d = 17-22Å) attributed to the (100) reflection in the polymer. The broad peak at 2θ = 20° (d = 4.4Å) should be assigned to the amorphous halo. On the basis of these results it was concluded that all the polymers had a pseudohexagonal (columnar) packing structures in the solid state. In addition, aging effect of polymer solution on molecular weight and molar ellipticity were investigated. In result, CD active polymers (poly(1) and poly(3)) showed higher stability than CD inactive polymers (poly(2) and poly(4)).

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We have already succeeded in synthesizing a poly(9,10-anthryleneethynylene) with pendant phenoxyl radicals at the 2- and 7-positions which has high durability to spin defects and a large average S value (S = 5/2) corresponding to the ferromagnetic spin coupling network spreading throughout the ≥-conjugated chain. The coplanarity of ≥-conjugated pendant polyradicals throughout the backbone chain and pendant side chain is significantly effective in the magnitude of the spin polarization and the spin-exchange coupling constant. In this study, we synthesized the corresponding dimer models to discuss the electronic and magnetic properties of the polyradical related to the conformation using UV/vis and fluorescence spectra, ESR and CV in various solvents. The UV/vis spectrum of the dimer showed a broad absorption peak at 488 nm in chloroform. On the other hand, the absorption peak showed narrowing, and a new peak appeared at 520 nm in heptane, dodecane, methanol and cyclohexane. The peaks at 488 nm and 520 nm were attributed to the oligo(anthryleneethynylene) chromophore with twisted and coplanar conformations, respectively. The temperature dependence of UV/vis spectra indicated the grand state of twisted conformation in chloroformand that of coplanar conformation in heptane.

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A Phthalocyanine Zinc (II) (ZnPc) / Nafion (Nf) hybrid film was prepared by casting the mixture solution of ZnPc and Nf, and a reversible association-dissociation of ZnPc in the Nf film was studied using a UV-visible absorption spectroscopic technique. It was found that a zinc phthalocyanine dimer in the film is dissociated reversibly to form the monomers when the Nf / ZnPc film is dipped in a 0.1 M LiCl electrolyte solution (pH = 7). The dissociation rate increased with the concentration of cations such as Li +, Na+, and K+. We present thermodynamic and kinetic discussions about the reversible association-dissociation of ZnPc in the film.

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The degradability of chiral helical poly(4-dodecyloxy-3,5- bis(hydroxymethyl)phenylacetylene) (poly(DoDHPA)) and poly((-)-4- (dimethylpinanylsilyl)phenylacetylene (poly(PSPA) was investigated. In THF solution, the chiral helical structure of poly(DoDHPA) was more stable than that of poly(PSPA). On the other hand, poly(DoDHPA) membrane degraded faster than poly(PSPA) membrane in water or methanol. The degradability of poly(DoDHPA) membrane in poor solution was unexpected for us. In addition, the membrane immersed in water included the degraded compound more than that immersed in methanol. From 1H and 13C NMR measurement, it was found the degraded compound had a ring structure, the fact suggests the degradation on the main chain occurred together with cyclization.

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Poly(4-dodecyloxy3,5-bis(hydroxymethyl)phenylacetylene) had one-handed helicity in the main chain. To immobilize the chiral helical structure, transformation of the hydrogen bonds between side groups, which stabilizes the helicity to covalent bonds, was carried out by condensation with dichlorodimethylsilane. In IR spectra of the resulting polymers, new peaks attributed to Si-O-C bond appeared and a band attributed to O-H band became weaker. The molar ellipticity of the fixed polymers hardly decreased when the polarity of solvent increased.

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Polyradical possessing a one-handed helical structure would promise interesting magnetic and chiroptical properties. In this study, we have newly synthesized a poly(1,3-phenyleneethynylene)-based polyradical bearing galvinoxyl and dimethyl(10-(1S)-pinanyl)silyl group. The hydrogalvinoxyl precursor polymer was given by polymerization of (1,3-diiodophenyl)hydrogalvinoxyl and 1,3-diethynyl-5-[dimethyl(10-(1S)-pinanyl)silyl]benzene using Pd(PPh 3)4 catalyst (yield = 87%, Mn = 4.7 × 104, Mw/Mn = 4.1). The polymer yielded the corresponding polyradical with high spin concentration by treatment of the polymer solution with PbO2. In the CD spectrum taken in ethyl acetate solution, clear Cotton effects were observed in the absorption region of the backbone and hydrogalvinoxyl chromophore, indicating an excess of one-handed helical foldamer conformation, while no Cotton effects were observed in chloroform, THF and benzene solution. However, the Cotton effects appeared in CD spectra of the polymer and polyradical by addition of methanol to the chloroform solution. On the other hand, in the MCD spectra of the polymer and polyradical taken in chloroform solution, Faraday effects were observed in the absorption region of the backbone and galvinoxyl chromophore.

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Synthesis of chiral poly(phenyleneethynylene) membranes containing chiral menthyl or pinanyl silyl groups were examined. Their chiral helical main-chain structures were observed by CD measurement and removal of the chiral group from the chiral helical membranes were attempted. The polymer had a fairly high molecular weight(Mw = 4×l04) and gave a self-supporting membrane easily by solution casting method. In the CD spectrum of the polymer in CHCl3 / benzene, the Cotton signal increased as the content of benzene increased.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Phthalocyanine zinc(II) (ZnPc) was found to be adsorbed well into a Nafion (Nf) film. The kinetic analysis suggested that the adsorption of ZnPc into the Nf film is controlled by its diffusion in the Nf film with a diffusion coefficient of D = 1.9 x 10(-6) cm(2) s(-1) that is higher than those (10(-9)-10(-12) cm(2) s(-1)) of cationic redox molecules in the Nf film by 3-6 orders of magnitude. The adsorption isothermal was analyzed by a Brunauer-Emmett-Teller (BET) equation suggesting multilayer adsorption of ZnPc into the film. The BET analysis provided the amount of ZnPc for monolayer adsorption (w(m) = 1.50 x 10(-7) mol cm(-2)), from which the effective area for the ZnPc adsorption was estimated to be larger by a factor of 1.7 x 103 than the Nf film area (1.0 cm(2)). The absorption spectra of a Nf film adsorbing ZnPc ((Nf/ZnPc)(ads) film) exhibited two broad absorption bands at 385 and 680-750 nm without any structural features, which is significantly different from the absorption spectra of either ZnPc solution in DMF or a (Nf/ZnPc)(mix) film prepared from a DMF solution containing Nf and ZnPc by solvent evaporation. This is ascribed to the formation of a ZnPc aggregate in the (Nf/ZnPC)(ads) film. Photoluminescence data for the (Nf/ZnPc)(mix) film suggested the presence of a ZnPc monomer and dimer at equilibrium in the film with a concentration of 0.1 M and that energy transfer occurs from the monomer to the dimer in excitation of the monomer (at A x = 609 nm) to yield emission from the dimer. By contrast, photoluminescence data for the (Nf/ZnPc)(ads) film suggested that the excited ZnPc is self-quenched significantly by the formation of the ZnPc aggregate in the film. The lesser electroactivity of ZnPc in the (Nf/ZnPc)(ads) film compared with that in the (Nf/ZnPc)(mix) film could be ascribable to more difficult diffusion of ZnPc in the former film due to the formation of the ZnPc aggregate. The adsorption of ZnPc into the Nf film was significantly regulated by simple pretreatments of the Nf film such as immersion in solvents and storage under solvent vapors. The regulation was explained by controlled physical and chemical properties of a channel for mass and ion transport that is formed by sulfonate groups, countercations, and solvent molecules in the Nf film.

DOI： 10.1021/jp052218j

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We synthesized monodisperse oligo(9,10-anthryleneethynylene)s with pendant phenol residues at the 2- and 7-positions. The absorption maxima of oligomers shifted to longer wavelength with the degree of polymerization, suggesting a developed pi-conjugation correlated with the chain length. The static magnetic susceptibility of the dimeric radical was measured using a SQUID magnetometer, and the 2J (J: spin coupling constant through the dianthrylacetylene unit) value of the dimeric radical was 34 cm(-1), which agreed with the 2J value of the corresponding 2-substituted dimeric radical (31 cm(-1)). These large 2J values of the dimeric radicals can be explained from less steric hindrance between the side chain radicals and the backbone. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polt.2005.03.127

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

{4-[(3,5-Di-tert-butyl-4-hydroxyphenyl)(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dienylidene)methyl] phenyl}acetylene (abbreviated as (4-ethynylphenyl)hydrogalvinoxyl) was polymerized using [Rh(norbornadiene)Cl](2) catalyst in the presence of (R)-1-phenylethylamine or (S)-1-phenylethylamine to give red polymers. The circular dichroism (CD) spectra of polymers indicated that an excess of one-handed helical polyacetylene backbone was induced by helix-sense-selective polymerization under the asymmetric condition despite the achiral monomer. Results show that the CD signal intensity depends on temperature and decreases reversibly with increasing temperature, although the energy difference between the right-handed and left-handed conformations of each other is almost zero. The sign of the CD signal in the absorption region (420 nm) of the hydrogalvinoxyl chromophore, which was calculated from the polymer geometry, suggests that the excess of right-handed helix was induced by polymerization in the presence of (R)-1-phenylethylamine.

DOI： 10.1021/ma050864a

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Two new chiral helical poly(hydroxyl-containing phenylacetylene) membranes without the coexistence of any other chiral moieties were prepared in the following manner: (1) synthesis and homo-or copolymerization of two new chiral pinanylsiloxy-containing phenylacetylenes, (2) preparation of self-supporting membranes from the (co)poly(chiral pinanylsiloxy-containing phenylacetylene)s by a solvent-casting technique, and (3) depinanylsilylation of the preformed polymer membranes in situ. Complete depinanylsilylation was successfully achieved by treating with trifluoroacetic acid. The resulting membranes exhibited circular dichroism despite the absence of the chiral substituents, a fact indicating that the main chains of the polymers retained their chiral helicity. This is the first method to synthesizing such chiral poly(phenylacetylene) membranes. Since the membranes maintained their self-supporting properties, we were able to use them as enantioselective separation membranes in the permeation of an aqueous solution of a racemate. As a result, the importance of the contribution of the chiral main chain on enantioselective permeation was directly confirmed for the first time. In addition, since some of the depinanylsilylated membranes were insoluble in organic solvents, we could use them as an separation membrane for a toluene solution of a racemate.

DOI： 10.1021/ma0500898z

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

An achiral and bulky phenylacetylene monomer, (4-ethynyl-phenyl)hydrogalvinoxyl), was polymerized using [Rh(nbd)Cl](2) (nbd = 2,5-norbornadiene) catalyst in chiral phenylethylamine. The circular dichroism (CD) spectra of the obtained polymers indicated that an excess of one-handed helical polyacetylene backbone was induced by helix-sense-selective polymerization despite the achiral monomer.

DOI： 10.1246/cl.2005.854

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

We synthesized two kinds of chiral polystyrene-based monoliths, which are macroporous gel with continuous open-celled monolith structure. Thus, two chiral styrene monomers, (-)-p-[dimethyl(10-pinanyl)silyl] styrene ((-)-PSSt) and (-)-p-(menthoxycarbonyl)styrene ((-)-MtSt]), were prepared and subjected to water-in-oil emulsion polymerization in the presence of divinylbenzene and AIBN. The macroporous structure of the obtained monoliths was directly confirmed by SEM observation. The obtained monoliths showed an optical resolution ability. That is, in the enantioselective adsorption using trans-stilbene oxide, poly[(-)-PSSt] monolith and poly[(-)-MtSt] monoliths preferentially adsorbed (SS)-isomer [poly[(-)-PSStl monolith: α((S,S)) = 1.49 (0.25 wt % acetone solution); poly[(-)-MtSt] monolith: α((S,S)) = 1.39 (0.25 wt % toluene solution)]. Depinanylsilylation of the poly[(-)-PSStl monolith and removal of menthyl groups from the poly[(-)-MtSt] monolith were achieved by acid-catalyzed. scission of the Si-C bond and base-catalyzed hydrolysis, respectively. In addition, de-poly[(-)-PSSt] and de-poly[(-)-MtSt] showed enantioselectivity ((SS)-isomer preferentially absorbed) in adsorption using trans-stilbene oxide in spite of the absence of chiral substituents in the monoliths. © 2005 Wiley Periodicals, Inc.

DOI： 10.1002/pola.20645

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：SOC POLYMER SCIENCE JAPAN  

A new porous ion exchange resin having an open-celled monolith structure was prepared and its ion exchange properties were examined. The new ion exchange resin was found to have the following advantages over the conventional ion exchange resins having bead structures. First, the new ion exchange resin has a high adsorption ability for the ions having low selectivity coefficients, and the ion exchange band length is smaller than that of the conventional resins. Second, in an electric field, the rejection time of the ions adsorbed to the new ion exchange resin was about one twentieth of that of the ions containing the conventional resins. These specific properties of the new ion exchange resin are attributable to the quantitative introduction of ion exchange groups into the resin having a uniform open-celled monolith structure.

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Society of Polymer Science  

A new porous ion exchange resin having an open-celled monolith structure was prepared and its ion exchange properties were examined. The new ion exchange resin was found to have the following advantages over the conventional ion exchange resins having bead structures. First, the new ion exchange resin has a high adsorption ability for the ions having low selectivity coefficients, and the ion exchange band length is smaller than that of the conventional resins. Second, in an electric field, the rejection time of the ions adsorbed to the new ion exchange resin was about one twentieth of that of the ions containing the conventional resins. These specific properties of the new ion exchange resin are attributable to the quantitative introduction of ion exchange groups into the resin having a uniform open-celled monolith structure.

DOI： 10.1295/koron.62.7

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

We synthesized one-handed helical poly[(4-ethynylphenyl)hydrogalvinoxyl] (poly(EPHG)) by helix-sense-selective polymerization using [Rh(nbd)Cl] 2 and [Rh(cod)Cl]2 catalyst in the presence of (R)-(+)-1- or (S)-(-)-1phenylethylamine (PEA). The [Rh(cod)Cl]2catalyst system gave red polymers whose CD spectra showed the stronger Cotton effect though the yield (2∼3%) and molecular weight (Mn = 1.1∼104) were lower than those of polymers obtained by [Rh(nbd)Cl]2. The CD patterns of polymers obtained by [Rh(nbd)Cl]2and [Rh(cod)Cl] 2were mirror image of each other in spite of the same chiral condition, i.e. in the presence of (R)-PEA. This fact indicates that the helix sense on the helix-sense-selective polymerization was able to be controlled by the bulkiness of achiral diene ligand.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

The stability, stimuli-responsibility and degradability of chiral helical poly(4-dodecyloxy-3,5-bis(hydroxymethyl)phenylacetylene) (poly(DHPA)) were investigated. In solution, the molar ellipticity of poly(DHPA) ([θ]) depended on temperature or the polarity of solvent. This findings suggested the chiral helical structure was maintained by only intramolecular hydrogen bonds between neighboring side chains. In solid states, the weight-average molecular weight (Mw) of poly(DHPA) unchanged until 200deg
C, and no [θ] was observed when Mw was under 1.0 × 105.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

Two new chiral helical poly(hydroxyl-containing phenylacetylene) membranes without the coexistence of any other chiral moieties were prepared in the following manner: 1) Synthesis and homo- or co-polymerization of two new chiral pinanylsiloxy-containing phenylacetylenes, 2) Depinanylsilylation of the preformed polymer membranes in-situ. Complete depinanylsilylation was successfully achieved by treating with trifluoroacetic acid. The resulting membranes exhibited circular dichroism despite the absence of the chiral substituants, the fact indicating that the main chains of the polymers retained their chiral helicity. This is the first method to synthesizing such chiral poly(phenylacetylene) membranes. Furthermore we examined enantioselective permeation by using the obtained membranes. As a result, the importance of the contribution of the chiral main chain on enantioselective permeation was directly confirmed for the first time. In addition, since some of the depinanylsilylated membranes were insoluble in organic solvents, we could use them as an separation membrane for a toluene solution of a racemate.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

We synthesized chiral/achiral phenylacetylenes with two hydroxyl groups and obtained copolymers in various feed ratios. The copolymers showed large specific rotation and strong Cotton effect even in small chiral monomer contents. This phenomenon can be explained by the "sergeants and soldiers" effect and might be attributed to the transport of the chiral information into the entire main chain because of the enhanced chain rigidity through intramolecular hydrogen bonds. In the CD spectrum of poly(phenylacetylene) having chiral pinanyl groups and two hydroxyl groups (poly(1)), the Cotton signal showed a reversible shifting as changing the polarity of solvent Poly(1) afforded a free-standing membrane by solution casting method, and then we carried out the desilylation of poly(1) in the membrane state to obtain the chiral helical poly(phenylacetylene) membrane without the coexistence of any other chiral source. The desilylated polymer membranes showed enantioselective permabilities despite the absence of the chiral groups due to the presence of the helical main chain.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

Achiral phenylacetylenes(RHPA) having two hydroxymethyl groups and an alkyloxy group of various chain length and shaps (R = n-octyl(Oc), n-decyl(De), n-undecyl(U), n-dodecyl(D), 2-ethylhexyl(EH), 4-methylpentyl(MP)) in 4-position were synthesized. These monomer were polymerized using a chiral catalytic system. Polymers of OcHPA, DeHPA, UHPA, and DHPA obtained Cotton effects at wavelengths around 430nm and 307nm in CD (Fig. 1) indicating the main-chains have a chiral helical conformation. It was found that these monomers were suitable for the helix-sense-selective polymerization. The molar ellipticity values([θ]) of Poly(DHPA) and poly(OcHPA) were very similar and [θ] of poly(UHPA) showed smaller than that of poly(DHPA). Although the pendant alkyl groups of poly(OcHPA) and poly(EHHPA) had the same carbon numbers, poly(OcHPA) with linear alkyl chains was soluble and poly(EHHPA) with branched alkyl chains was insoluble, suggesting that the more than eight of the carbon number of the backbone in the alkyl groups are needed to prevent the polymer chains from interacting with each other with hydrogen bonds.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

We have investigated in detail the effect of the bulkiness of catalyst, and monomers on the helix-sense-selective polymerization of (4-ethynylphenyl) hydrogalvinoxyl (EPHG) using the Rh-catalyst in the presence of optically active 1-phenylethylamine (PEA). Monomers EPAcG and EPPEAG, whose hydroxyl group was protected by acetyl group or (R)-PEA moiety compared to EPHG, polymerized as well to give poly(EPAcG) and poly(EPPEAG), respectively, which showed clear and similar Cotton effects in tetrahydrofuran solution. The CD patterns of polymers obtained by [Rh(nbd)Cl] 2 and [Rh(cod)Cl] 2 were mirror image of each other in spite of the same chiral condition, i.e. in the presence of (R)-PEA. This fact indicates that the helix sense was controlled by achiral diene-ligands.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

We synthesized chiral helical polymeric membranes containing carboxyl/amino groups by in-situ desubstitution of poly(phenylacetylenes) membranes having chiral ester/carbamate moieties. The resulting membranes exhibited circular dichroism despite the absence of the chiral substituents, the fact indicating that the main chains of the polymers retained their chiral helicity. Furthermore we examined enantioselective permeation of various racemic amino acid (0.50 wt% aqueous solutions) by using the obtained membranes containing carboxyl/amino groups. The desubstituted membranes showed enantioselectivity in the permeation of racemic amino acid. This result indicates that chiral helicity of the polymers were retained despite the absence of the chiral substituents. The desubstituted polymeric membranes having carboxyl/amino groups showed larger permeability coefficients in the permeations of hydrophilic amino acids.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

Phthalocyanine Zinc (II) (ZnPc) was found to be adsorbed well into a Nafion (Nf) film. The adsorption isothermal was analyzed using BET equation suggesting a multi-layer adsorption mode. The adsorption of ZnPc into the Nf film was significantly regulated by simple pretreatments of the Nf film such as immersing in solvents and storage under solvent vapors. The regulation was explained by tunable physical and chemical properties of hydrophilic ionic cluster region formed by sulfonate groups, counter cations and solvent molecules for mass and ion transport in the Nf film.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

The stability, stimuli-responsibility and degradability of chiral helical poly(4-dodecyloxy-3,5-bis(hydroxymethyl)phenylacetylene) (poly(DHPA)) were investigated. In solid states, the weight-average molecular weight and the molar ellipticity ([θ]) of poly(DHPA) significantly decreased at the range of 200 to 225°C which was higher temperature than other poly(phenylacetylene)s bearing no hydrogen bonds. In solution, [θ] of poly(DHPA) depended on temperature or the polarity of solvent. Poly(DHPA) was less degradable in air than similar poly(phenylacetylene)s having octyloxy or decyloxy groups on 4-position.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

We synthesized chiral/achiral phenylacetylenes with two hydroxy groups and obtained copolymers in various feed ratios. The copolymers showed large specifie rotation and strong Cotton effect even in small chiral monomer contents. This phenomenon can be explained by the "sergeants and soldiers" behavior and might be attributed to the transport of a chiral information into the entire main chain because of the enhanced chain rigidity through intramolecular hydrogen bonds. For comparison, we also report on the optical properties of the poly(phenylacetylene) containing methyl groups instead of hydroxymethyl groups.

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Language：Japanese   Publishing type：Research paper (international conference proceedings)  

4-Dodecybxy-3,5-bis[(dimethyl)hydroxysilyl]phenylacetylene (DHSPA) was synthesized and copolymeried with 4-dodecybxy-3,5-bisChydroxymethy]) phenylacetylene (DHPA) using a chiral catalytic system. To fix the chiral helical structure of the obtained copolymers, condensation between silanol and alchol was carried out. In IR spectra of the resulting copolymer, new peaks attributed to Si-OSi and Si-OC bonds appeared. The molar ellipticity of the resulting copolymer hardly decreased when the polarity of solvent increased (CHCl3/DMSO = 10/1). The finding suggested the chiral helical structure was maintained by covalent bonds, Si-OSiorSi-OC.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

We have examined the role of the chiral amine cocatalyst in the recently discovered helix-sense-selective polymerization of a phenylacetylene using a catalytic system consisting of an achiral rhodium complex ([Rh(norbornadiene)Cl](2)) as the catalyst and a chiral amine as the cocatalyst. Several chiral amines were effective for the polymerization reaction and their effectiveness depended on their bulkmess and coordination ability to rhodium. The sense selectivity of the polymerization increased with the concentration of the chiral amines. To discuss the structure of the true active species in the catalytic system, we have synthesized a new chiral rhodium complex having two chiral amines as ligands ([Rh (norbomadiene) (chiral amine)(2)]+BF4-). The isolated chiral complex also catalyzed the helix-senses-elective polymerization. These findings suggest that a chiral rhodium complex having two chiral amines may be the true active species when using the catalytic system consisting of [Rh(norbornadiene)Cl](2) and a chiral amine. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2004.09.046

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

To develop better polymeric materials for optical-resolution membranes, we synthesized nine chiral phenylacetylenes containing pinanyl groups. We used them to investigate the effects of chemical structures, including the number and position of the chiral groups in the monomers, on the induction of chirality in the main chain during polymerization and on the degree of enantioselectivity in the permeation of the polymeric membranes. The monomers included six new chiral p-(oligomethylpinanylsiloxanyl)phenylacetylenes. The homopolymerizations of these nine monomers with a Rh complex produced high-molecular-weight polymers (molecular weight = 10(5)-10(6)). Of the five polymers with a chiral pinanyl group at the 1-position of each oligosiloxanyl group, all except for two polymers showed high molar ellipticity in the main-chain region in the circular dichroism spectra. This finding indicated that these polymers had a chiral helical main chain. The membranes fabricated from all the polymers synthesized in this study were high-quality, except for two polymers. All these membranes showed enantioselective permeabilities for two amino acids and an alcohol. The membranes from the polymers with a chiral helical backbone, a high content of pinanyl groups, no oligodimethylsiloxane moieties, or a combination of these showed good enantioselectivities ( = 1.7-640) in permeation. We propose that the sense of the main-chain helicity determined the selectivity. (C) 2004 Wiley Periodicals, Inc.

DOI： 10.1002/pola.20356

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

We succeeded in introducing cation exchange groups quantitatively into a porous resin having an open-celled monolith structure. The resulting new cation exchange resin had the following advantages compared with conventional ion exchange resins having a bead structure. First, it was easier to pack it in a column. Second, the ion exchange rate of the new cation exchange resin was much higher than that of the conventional ion exchange resins, and the ion exchange band length of the new resin was smaller than that of the conventional ones. In addition, the electric conductivity was about five times higher than that of the conventional ones, although they had similar ion exchange capacities. These unique properties of the new cation exchange resin were caused by the quantitative introduction of ion exchange groups into the resin having the open-celled monolith structure. (C) 2003 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2003.10.097

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Society of Polymer Science  

We successfully introduced ion exchange groups quantitatively into a porous resin having an open-celled monolith structure. The resulting new ion exchange resin had the following advantages compared with conventional ion exchange resins having a bead structure. First, it was easier to pack it in a column. Second, the ion exchange rate of the new ion exchange resin was much higher than that of the conventional ion exchange resins, and the ion exchange band length of the new resin was smaller than that of the conventional ones. Third, the electric conductivity was about five times higher than that of the conventional ones, although they had similar ion exchange capacities. These unique properties of the new ion exchange resin were attributable to the quantitative introduction of ion exchange groups into the resin having the open-celled monolith structure. In addition, many kinds of ion-excharge resin monoliths from soft ones to hard ones were able to be prepared by changing the ratio of DVB.

DOI： 10.1295/koron.61.301

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：SOC POLYMER SCIENCE JAPAN  

We successfully introduced ion exchange groups quantitatively into a porous resin having an open-celled monolith structure. The resulting new ion exchange resin had the following advantages compared with conventional ion exchange resins having a bead structure. First, it was easier to pack it in a column. Second, the ion exchange rate of the new ion exchange resin was much higher than that of the conventional ion exchange resins, and the ion exchange band length of the new resin was smaller than that of the conventional ones. Third, the electric conductivity was about five times higher than that of the conventional ones, although they had similar ion exchange capacities. These unique properties of the new ion exchange resin were attributable to the quantitative introduction of ion exchange groups into the resin having the open-celled monolith structure. In addition, many kinds of ion-exchange resin monoliths from soft ones to hard ones were able to be prepared by changing the ratio of DVB.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/ma035493h

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Charge transport (CT) in a Nafion film incorporating [(NH3)(5)Ru(mu-pz)Ru(NH3)(5)](4+) ([Ru-II-Ru-II](4+); pz = pyrazine) was studied using a double potential-step chronoabsorptometry (DPSCA) technique. The oxidative CT by [Ru-II-Ru-II](4+)/[Ru-II-Ru-III](5+) (in a potential step from -0.2 to 0.3 V; first step) was compared with that by [Ru-II-Ru-III](5+)/[Ru-III-Ru-III](6+) (in a successive potential step from 0.3 to 0.7 V; second step). The predominant CTs by a physical displacement mechanism of the complexes were suggested for both of the steps. However, the rate constant of the CT for the first step was 5.2 time higher than that for the second step at 25 degreesC. The results on CT kinetics and dynamics revealed that the CTs in both of the steps are entropy-controlled in the activation at room temperature. The DeltaH(double dagger) (12 kJ mol(-1)) for the physical displacement in the second step was lower than that (24 kJ mol(-1)) for the first step, showing that the physical displacement for the second step is enthalpically favorable compared with that for the first step. The corresponding DeltaS(double dagger) (-234 J K-1 mol(-1)) for the second step is lower than that (DeltaS(double dagger) = -184 J K-1 mol(-1)) for the first step, making the physical displacement for the second step more entropically difficult than that for the first step. The entropy effect on the physical displacement was discussed on the basis of the interaction of the complexes with Nafion and reorganization of the solvent (water) molecule involved in the process. The DeltaS(double dagger) for the physical displacement of redox complexes in the film decreased with the positive charge of the complexes, suggesting that the highly positive-charged complex is entropically unfavorable for physical displacement, presumably due to higher degree of solvation of the complex and the sulfonate groups in their dissociation.

DOI： 10.1021/jp036146c

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We synthesized monomers of poly(9,10-anthryieneethynylene)s which were anthracene derivatives substituted with one or two phenol residues at the P-position. The monomers were polymerized by Pd(0) catalyst to give the corresponding precursor polymer with (M) over bar (n) approximate to 5 X 10(3). The polyradicals were synthesized by oxidation of the hydroxyl group. The magnetization plots of the polyradicals showed that the average ground state spin quantum number of the polyradical with two pendant phenoxyls in one anthracene unit (S = 5/2) became larger than that of the polyradical with one pendant phenoxyl (S = 2/2) at the same spin concentration (spin cone.;approximate to 0.35 spin/phenoxyl unit). The statistical simulation of the ground spin states supported that this behavior was caused by ladder-like spin coupling network of the polyradical with two pendant phenoxyls in one anthracene unit. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0277-5387(03)00251-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/ja021233o

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A poly(9,10-anthryleneethynylene)-based polyradical with two pendant stable phenoxyls in one anthracene skeleton was newly synthesized via polymerization of the corresponding bromoethynylanthracene monomer using a Pd(0) catalyst. The average molecular weight of the polymer reached (M) over bar (n) = 5 x 103 and was soluble in common organic solvents. The polyradical was prepared from the corresponding hydroxyl precursor polymer and was appropriately stable at room temperature. The ESR spectrum of the corresponding monomeric radical suggested an effectively delocalized spin density distribution on the backbone anthracene. The magnetization and the static magnetic susceptibility of the polyradical were measured using a SQUID magnetometer. The large average spin quantum number ((S) over bar = 5/2) of the polyradical indicated that the ferromagnetic spin coupling network of the polyradical had spread throughout the pi-conjugated chain and that it was considerably insensitive to spin defects.

DOI： 10.1021/ja026929w

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARCEL DEKKER INC  

Polymerization of two dipherylacetylenes having a ferrocenyl group at para or meta position, 1-[p-ferrocenylphenyl]-2-phenylacetylene (p-FcDPA) and 1-[m-ferrocenylphenyl]-2-phenyl-acetylene (m-FcDPA) and properties of the formed polymers were investigated. Both monomers polymerized with TaCl5-n-Bu4Sn catalyst in good yields to give reddish brown polymers. Poly(p-FcDPA) was insoluble in any solvents. On the other hand, poly(m-FcDPA) was soluble in CHCl3, THF, anisole, o-dichlorobenzene, and so on, and its weight-average molecular weight (M-w) was 53 x 10(4) and fairly high. A free-standing film of poly(m-FcDPA) could be easily fabricated by solution casting. The onset temperature of weight loss (T-0) of poly(m-FcDPA) in air was ca. 310degreesC, indicating moderate thermal stability. Poly(m-FcDPA) was electrochemically active, and showed redox cycles based on the ferrocene moiety in cyclic voltammetry.

DOI： 10.1081/MA-120017255

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

The gas permeability and n-butane solubility in glassy poly(1-trimethyl-germyl-1-propyne) (PTMGP) are reported. As synthesized, the PTMGP product contains two fractions: (1) one that is insoluble in toluene and soluble only in carbon disulfide (the toluene-insoluble polymer) and (2) one that is soluble in both toluene and carbon disulfide (the toluene-soluble polymer). In as-cast films, the gas permeability and n-butane solubility are higher in films prepared from the toluene-soluble polymer (particularly in those films cast from toluene) than in films prepared from the toluene-insoluble polymer and increase to a maximum in both fractions after methanol conditioning. For example, in as-cast films prepared from carbon disulfide, the oxygen permeability at 35 degreesC is 330 x 10(-10) cm(3) (STP) cm/(cm(2) s cmHg) for the toluene-soluble polymer and 73 x 10(-10) cm(3) (STP) cm/(cm(2) s cmHg) for the toluene-insoluble polymer. After these films are conditioned in methanol, the oxygen permeability increases to 5200 x 10(-10) cm(3) (STP) cm/(cm(2) s cmHg) for the toluene-soluble polymer and 6200 x 10(-10) cm(3) (STP) cm/(cm(2) s cmHg) for the toluene-insoluble polymer. The rankings of the fractional free volume and nonequilibrium excess free volume in the various PTMGP films are consistent with the measured gas permeability and n-butane solubility values. Methanol conditioning increases gas permeability and n-butane solubility of as-cast PTMGP films, regardless of the polymer fraction type and casting solvent used, and minimizes the permeability and solubility differences between the various films (i.e., the permeability and solubility values of all conditioned PTMGP films are similar). (C) 2002 Wiley Periodicals, Inc.

DOI： 10.1002/polb.10276

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DOI： 10.1021/ma011537f

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Azobenzene-containing polyacetylenes, poly[(4-butoxyphenyl)(4-ethynylphenyl)diazene] [poly(BuOEAB)] and poly[4-(4-ethynylphenylazo)benzoic acid hexyl ester] [poly(HexOCOEAB)] with number-average molecular weights ranging from 2,800 to 104,000 were synthesized by the polymerization of the corresponding acetylene monomers by [RhCl(norbornadiene)](2) catalyst in conjunction with Et3N, Ph2C=C(Ph)Li, and PPh3 as cocatalysts in toluene and THF in good yields. The polymers exhibited thermogravimetric curves with inflection points corresponding to cleavage of butyl ether and hexyl ester groups. The trans-azobenzene moiety of poly(BuOEAB) isomerized into cis-form upon UV-irradiation at the wavelength of 300-400 nm both in solution and in the filmy state. Oil the other hand, poly(HexOCOEAB) did not isomerize under the same condition.

DOI： 10.1081/MA-120013572

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.1295/kobunshi.50.92

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Photochromic characteristic and optical molecular reorientation in conducting polymers such as polyacetylene and poly(p-phenylenevinylene) derivatives containing photochromic azobenzene moieties in the side chain have been studied. Upon irradiation of a linearly polarized light on these films, accompanying with trans-cis isomerizasion of azobenzene, optical anisotropy is induced.

DOI： 10.1016/S0379-6779(00)00692-5

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Gas permeation, sorption, and structural properties of two highly branched polyacetylenes, poly [1-phenyl-2-[p-(triphenylsilyl)phenyl] acetylene] (PPhSiDPA) and poly [1-phenyl-2-[p-(triisopropylsilyl)phenyl] acetylene] (PPrSiDPA), are reported. Structurally, both polymers have much in common; however, their transport properties are quite different. PPhSiDPA has dramatically lower permeability coefficients than PPrSiDPA. For example, the Oz permeability coefficients of PPhSiDPA and PPrSiDPA are 12 x 10(-10) and 230 x 10(-10) cm(3) (STP) cm/(cm(2) s cmHg), respectively at 22 degreesC. Gas solubility is very high in PPrSiDPA, similar to that observed in poly(1-trimethysilyl-1-propyne) (PTMSP), the most permeable polymer known. Gas solubility coefficients of PPhSiDPA are 2-3 times lower than those of PPrSiDPA. Free volume size and size distribution were characterized using positron annihilation lifetime (PAL) spectroscopy. Results from these studies (i.e., a bimodal size distribution of free volume elements and large free volume element size) are consistent with the observed transport and sorption properties of PPrSiDPA. In contrast, the PAL spectrum of PPhSiDPA is similar to that of conventional low free volume glassy polymers.

DOI： 10.1021/ma000628u

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

Exciton dynamics in luminescent poly(diphenylacetylene) (PDPA) derivatives with different substituents have been studied by time-resolved photoluminescence (PL) spectroscopy. Although their absorption and PL spectra are almost similar, PL of PDPA-nBu decays single-exponentially, whereas PL of PDPA-SiMe3 decays faster with a suppressed exponential decay function indicating exciton dissociation, In the case of PDPA-nBu mixed with a non-luminescent polyphenylacetylene (PPA) derivative, PL decay of PDPA-nBu is significantly shortened. The experimental results show the influences of side chains on exciton confinement in the backbone/main chain. Efficient PL in PDPA-nBu is a result of effective exciton confinement on the main chain, but excitons migration or energy transfer to another main chain segments may take places.

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We have studied the optical properties of thin films of novel disubstituted acetylene polymers such as poly(1-phenyl-2-p-n-butylphenylacetylene) (PDPA-nBu) and poly(1-n-hexyl-2-phenylacetylene) (PHxPA), that show high photoluminescence (PL) quantum efficiency in comparison with unsubstituted or monosubstituted polyacetylene. The polarization dependence of PL and Raman scattering of PDPA-nBu and PHxPA have been studied in order to clarify the emission mechanism. Assuming the model of short polyene conjugation length in the acetylene polymers, we estimate the average conjugation length from the respective stretching vibration frequency of the carbon double bond carbon double bond. The emission mechanism of PHxPA and PDPA-nBu is discussed in relation with the electronic excited states of these polymers.

DOI： 10.1016/S0379-6779(00)00523-3

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Poly(p-phenylene)-based novel conjugated polymers having photoisomerizable azobenzene units in the main chain were prepared by the palladium-catalyzed Suzuki coupling of 1,3-propanediol diesters of 1,4-phenylenediboronic acids with 4,4'-diiodoazobenzenes, and the reversible cis-trans isomerizations of azobenzene units were achieved. Despite their stiff structures, the polymers are soluble in common organic solvents such as chloroform, toluene, and tetrahydrofuran if either or both of the monomers possess n-hexyl side chains on the aromatic rings. The resulting polymers possess high molecular weights (M-n > 7 x 10(3)) and are thermally stable (T-0 > 350 degrees C) and fluorescent. The azobenzene units in the conjugated polymer backbone underwent the photochemical cis-trans reversible isomerizations in both tetrahydrofuran and toluene upon irradiation with UV light of appropriate wavelengths at 20 degrees C. The thermal cis-to-trans isomerization was also readily accomplished in toluene at 80 degrees C. Moreover, the solid-state photochemical trans-to-cis isomerization took place at 20 degrees C. These isomerization processes were accompanied by the change in the three-dimensional hydrodynamic volume of the polymer, which was evidenced by size exclusion chromatography.

DOI： 10.1021/ma0004559

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：John Wiley & Sons Inc  

The effects of film thickness, physical aging, and methanol conditioning on the solubility and transport properties of glassy poly[1-phenyl-2-[p-(triisopropylsilyl) phenyl]acetylene] are reported at 35 °C. In general, the gas permeability coefficients are very high, and this polymer is more permeable to larger hydrocarbons (e.g., C3H8 and C4H10) than to light gases such as H2. The gas permeability and solubility coefficients are higher in as-cast, unaged films than in as-cast films aged at ambient conditions and increase to a maximum in both unaged and aged as-cast films after methanol conditioning. For example, the oxygen permeability of a 20-μm-thick as-cast film is initially 100 barrer and decreases to 40 barrer after aging for 1 week at ambient conditions. After methanol treatment, the oxygen permeabilities of unaged and aged films increase to 430 and 460 barrer, respectively. Thicker as-cast films have higher gas permeabilities than thinner as-cast films. Propane and n-butane sorption isotherms suggest significant changes in the nonequilibrium excess free volume in these glassy polymer films due to processing history. For example, the nonequilibrium excess free volume estimated from the sorption data is similar for as-cast, unaged samples and methanol-conditioned samples
it is 100% higher in methanol-conditioned films than in aged, as-cast films. The sensitivity of permeability to processing history may be due in large measure to the influence of processing history on nonequilibrium excess free volume and free volume distribution. The propane and n-butane diffusion coefficients are also sensitive to film processing history, presumably because of the dependence of diffusivity on free volume and free volume distribution.

DOI： 10.1002/(SICI)1099-0488(20000601)38:11<1474::AID-POLB70>3.0.CO;2-6

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACS  

The pure-gas permeation and sorption properties of poly[1-phenyl-2-[p-(trimethylsilyl)phenyl]acetylene] [PTMSDPA] are presented and compared to those of poly(1-trimethylsilyl-1-propyne)[PTMSP], poly(4-methyl-2-pentyne) [PMP], and poly(1-phenyl-1-propyne) [PPP]. PTMSDPA is more permeable to large, condensable vapors (e.g., n-butane) than to small, permanent gases (e.g., hydrogen). Such behavior is also observed in PTMSP and PMP but not in PPP. PTMSDPA has lower fractional free volume (0.26) and gas permeabilities than PTMSP and PMP. However, relative to conventional glassy polymers, PTMSDPA is a highly permeable, high free volume, glassy material. For example, the oxygen permeability coefficient of PTMSDPA is 1200×10-10 cm3(STP)·cm/(cm2·s·cmHg) at 25 °C. As temperature increases, the permeability in PTMSDPA increases for light gases (helium, hydrogen, and nitrogen) and decreases for more condensable gases. In contrast, the permeabilities of PTMSP and PMP decrease with increasing temperature for both light gases and more condensable hydrocarbons, n-Butane and propane sorption isotherms for PTMSDPA are concave to the penetrant relative pressure axis, consistent with dual-mode sorption behavior. Hydrocarbon sorption levels decrease in the order PTMSP&gt
PMP&gt
PTMSDPA&gt
PPP, in agreement with the ranking of the fractional free volumes of the materials.

DOI： 10.1021/ma991566e

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：John Wiley and Sons Inc.  

Poly(phenylenevinylene)-based conjugated polymers with azobenzene groups in the main chains were prepared by the Pd-catalyzed coupling polymerization of divinylarenes with dihaloarenes. The Pd-catalyzed coupling polymerization of 4,4′-divinylazobenzene with dihaloarenes such as 1,3-dibromobenzene, 1,4-dibromo-2,5-dihexylbenzene, 4,4′-dibromoazobenzene, and 4,4′-diiodoazobenzene resulted in polymers with poor solubility. In contrast, soluble polymers containing azobenzene moieties in the main chains were attainable from divinylbenzenes with 4,4′-dihaloazobenzenes if either or both of the monomers possessed hexyl groups on the aromatic rings. The number-average molecular weight of the polymer exceeded 10,000 under optimized conditions, and the polymer showed a remarkably redshifted absorption in the visible region (456 nm). 1H NMR and IR spectra supported that the polymers having only trans-geometry for the double bonds. © 2000 John Wiley &amp
Sons, Inc.

DOI： 10.1002/(SICI)1099-0518(20000401)38:7<1057::AID-POLA2>3.0.CO;2-5

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARCEL DEKKER INC  

Copolymerization of 1-[3,5-bis(trimethylsilyl)phenyl]-2phenyl-acetylene (m,m-(Me3Si)(2)DPA) with other diphenylacetylene derivatives and their copolymer properties were investigated. Homopolymerization of m,m-(Me3Si)(2)DPA by TaCl5-n-Bu4Sn (1:2) did not give the polymer due to steric hindrance. However, m,m-(Me3Si)(2)DPA copolymerized with diphenylacetylene (DPA), 1-phenyl-2-[p-(trimethylsilyl)phenyl] acetylene (p-Me3Si DPA), and 1-phenyl-2-[m-(trimethylsilyl)phenyl]acety-lene (mMe(3)SiDPA) in the presence of TaCl5-n-Bu4Sn at various feed ratios to give copolymers in moderate yields. The formed copolymers were yellow to orange solids, which were soluble in common organic solvents such as toluene and CHCl3. The highest weight-average molecular weights (M-w) of these copolymers reached ca. 6 x 105 and tough films could be obtained by solution casting. Their onset temperatures of weight loss in air were observed around 400 degrees C, indicating high thermal stability. The oxygen permeability coefficients at 25 degrees C of copoly(m,m-(Me3Si)(2) DPA/DPA) (feed ratio 1.1) and copoly(m,m-(Me3Si)(2)DPA/pMe(3)SiDPA) (feed ratio 1:2) were 21 and 100 barrers, respectively, medium in magnitude among polymers from substituted acetylenes.

DOI： 10.1081/MA-100101147

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Copolymerization of diphenylacetylene having a hexaphenylbenzene group, 1-[p-(pentaphenyl)phenyl]-2-phenylacetylene (1), with a few other diphenylacetylene derivatives (i.e., diphenylacetylene, 1-phenyl-2-[p-(trimethylsilyl)phenyl]acetylene, 1-phenyl-2-[p-n-octylphenyl]acetylene, (2a-c, respectively) and properties of the formed copolymers were investigated. No polymer was obtained in homopolymerization of 1 with TaCl5-n-Bu4Sn catalyst owing to steric hindrance. On the other hand, copolymerization with 2a-c proceeded at various feed ratios to give copolymers in moderate yields. Copoly(1/2a) (feed ratio 25/75) was soluble in toluene and CHCl3 and its weight-average molecular weight (MW) was ca. 31 x 104 and relatively high. Copoly(1/2b) and copoly(1/2c) (both feed ratios 5/95) were soluble in common organic solvents, and had a large MW up to ca. 1 x 106. These copolymers were yellow to orange solids. Oxidative cyclodehydrogenation of hexaphenylbenzene groups in copoly(1/2a) was attempted in order to convert them into more conjugated groups.

DOI： 10.1007/s002890050600

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACS  

Polyacetylenes with azobenzene moieties [poly(3-ethynylazobenzene) and poly(4-ethynylazobenzene)] were obtained by polymerization using [(nbd)RhCl]2-Et3N. The results are the first example of synthesis of polyacetylenes with azobenzene moieties directly connected to the main chain. Though poly(4-ethynylazobenzene) was insoluble in any solvents, poly(3-ethynylazobenzene) was soluble in common solvents, had high molecular weight up to 4.9×105, and provided a free-standing film by solution casting. Trans-to-cis photoisomerization of azobenzene moieties in poly(3-ethynylazobenzene) was observed upon ultraviolet irradiation.

DOI： 10.1021/ma991326z

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A highly luminescent disubstituted polyacetylene, poly(1-phenyl-2-(Formula presented)-butylphenylacetylene) (Formula presented) and its blend with a poorly luminescent monosubstituted polyacetylene, poly(1-(Formula presented)-trimethylsilylphenylacetylene) (Formula presented), are studied by time-resolved photoluminescence (PL) spectroscopy. In pure (Formula presented) PL intensity at short wavelength decays faster than that at long wavelength, whereas PL spectra exhibit a dynamic Stokes shift to longer wavelengths with time. In blends of PDPA-(Formula presented) only PL originating from (Formula presented) is observed, without contribution from (Formula presented) The PL lifetime drastically decreases upon mixing a small amount of (Formula presented) in (Formula presented) The PL characteristics of pure (Formula presented) and its blend with (Formula presented) are discussed in terms of lattice/vibrational relaxation of the excitonic state and exciton migration. © 2000 The American Physical Society.

DOI： 10.1103/PhysRevB.61.10167

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

Three disubstituted acetylenes with an adamantyl group-1-(p-adamantylphenyl)-2-chloroacetylene (ClpAdPA), 1-(p-adamantylphenyl)-1-propyne (pAdPP), and 1-(p-adamantylphenyl)-2-phenylacetylene (pAdDPA)-polymerized in good yields in the presence of MoCl5- or TaCl5-based catalysts. The highest weight-average molecular weights of poly(ClpAdPA), poly(pAdPP), and poly(pAdDPA) reached 3.6 x 10(5), 1.1 x 10(6), and 6.0 x 106, respectively. The polymers were yellow to white solids and completely soluble in toluene, chloroform, and so forth. These polymers thermally were fairly stable, and the onset temperatures of weight loss in air were over 360 degrees C. Poly(pAdPP) and poly(pAdDPA) provided free-standing films by solution casting, and their oxygen permeability coefficients (P-O2) at 25 degrees C were 8.6 and 55 barrers [1 barrer = 1 x 10(-10) cm(3).(STP).cm/(cm(2).s.cm Hg)], respectively, which are relatively small compared to those of other substituted polyacetylenes. (C) 1999 John Wiley & Sons, Inc.

DOI： 10.1002/(SICI)1099-0518(19991215)37:24<4546::AID-POLA12>3.0.CO;2-R

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Local mobility of three substituted polyacetylenes was investigated by means of a quasielastic neutron scattering technique aiming at elucidating the origin of gas permeability of these polymers. It was found that the local flux, which is defined as the product of the relaxation rate Gamma, and the mobile fraction f(m), increases with the gas permeability coefficient. This suggests that the local flux is an important factor controlling gas permeability. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0032-3861(99)00257-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Japan Society of Applied Physics  

Monosubstituted polyacetylenes (PA), that is, poly(phenylacetylene) (PPA) derivatives with various substituents attached at the ortho-position of the phenyl ring, have been studied. The valence band top and the bandgap energy of these polymers were estimated in the range from -5.5 eV to -5.9 eV (vs vacuum level) and from 1.9 eV to 2.3 eV, respectively, depending on the substituents. Although PL of these PPA derivatives is very weak, we have observed electroluminescence (EL), which is considered to be related to the nature of the self-trapped excitonic states of these polymers. The EL characteristics were found to depend on the substituents of polymers. In the mixture of poly(o-trimethylsilylphenylacetylene) (PPA-oSiMe<SUB>3</SUB>) with the strong luminescent disubstituted PA, poly(1-phenyl-2-p-n-butylphenylacetylene) (PDPA-nBu), the enhancement of PL of PPA-oSiMe<SUB>3</SUB> was not observed. However, EL of PPA-oSiMe<SUB>3</SUB> was enhanced in the mixture with PDPA-nBu, which is explained in terms of excitation energy transfer.

DOI： 10.1143/JJAP.38.931

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Sci Ltd  

The spin probe technique was systematically applied to study a family of high permeability and high free volume glassy polymers. Rotation correlation times τ(c) or frequencies v = 1/τ(c) of 2,2,6,6-tetramethylpyperidine-1- oxyl (TEMPO) were measured in amorphous teflons random copolymers of tetrafluoroethylene and 2,2-bistrifluoromethyle-4,5-difluoro-1,3-dioxole, polyacetylenes and polynorbornenes. Polymers distinguished by unusually high, for the glassy state, permeability and free volume exhibit large rotational mobility of TEMPO. The correlation times correspond to fast rotation of the spin probe previously observed only in rubbery polymers. Correlations between the frequency v and gas permeability and diffusion coefficients were observed. However, in some polymers, the spin probe's rotation rate is also sensitive to side-chain local mobility, which does not affect translational diffusion coefficients of gas molecules in polymers.

DOI： 10.1016/S0032-3861(98)00395-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society  

Disubstituted acetylenes with chiral pinanyl groups, (-)-1-{4-[dimethyl(10-pinanyl)silyl]-phenyl}-2-phenylacetylene (1), (-)-1-{3-[dimethyl(10-pinanyl)silyl]phenyl}-2-phenylacetylene (2), (-)-1-{4-[dimethyl(10-pinanyl)silyl]phenyl}-1-propyne (3), and (-)-1-chloro-2-{4-[dimethyl(10-pinanyl)silyl]-phenyl}acetylene (4), polymerized with NbCl5-, TaCl5-, or MoCl5-based catalysts to give high molecular weight polymers in good yields. Poly(1) and poly(2) showed intense circular dichroism (CD) effects in the UV-vis region and large optical rotations, which suggests that these polymers exist in helical conformations with an excess of one-handed screw sense. No significant decrease in the magnitude of CD effects of poly(1) and poly(2) with increasing temperature indicated the relatively high stability of their helical conformations. On the other hand, the intensities of CDs of poly(3) and poly(4) were approximately 1/10 those of poly(1) and poly(2), which means that introduction of two aromatic side groups into the repeating unit is favorable for the induction of helical conformation to disubstituted acetylene polymers. The free-standing membranes of poly(1), poly(2), and poly(3) exhibited characteristic properties as gas-permeable and optical resolution membranes. © 1999 American Chemical Society.

DOI： 10.1021/ma9810969

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Sequoia SA  

Electroluminescence (EL) and photoluminescence (PL) have been studied in polyacetylene derivatives with various substituents. Intense green and blue ELs are observed in poly(diphenylacetylene)s and in poly(1-alkyl-2-phenylacetylene)s, respectively. While, red PL and EL in mono-substituted polyacetylene derivatives are much weaker. Detailed dependence of EL and PL on molecular structure of substituents have been discussed. Spectral narrowing of PL and lasing have also been realized with intense excitation.

DOI： 10.1016/S0379-6779(98)01471-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Sequoia SA  

Photoluminescence (PL) and electroluminescence (EL) of mixtures of polyacetylene derivatives with different substituents have been studied in detail. Remarkable spectral shift of PL and EL from blue to green by changing the concentration of poly(diphenylacetylene) (PDPA) derivatives in poly(alkylphenylacetylene) (PAPA) derivatives has been observed. Marked quenching of PL and EL intensities has been found out in disubstituted polyacetylene such as PDPA derivatives upon introduction of monosubstituted polyacetylene. Dependence of PL decay time on molar ratio proportion of mixtures have been also studied. These characteristics have been discussed in terms of fast interchain interaction such as excitation energy transfer between polyacetylene derivatives with different molecular structures.

DOI： 10.1016/S0379-6779(98)01273-9

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We studied the excitation dynamics in films of disubstituted polyacetylene, a degenerate ground-state conjugated polymer, using psec transient and steady-state spectroscopies. The polymer is found to support charged and neutral topological soliton excitations concurrent with a strong intrinsic photoluminescence band with quantum efficiency, η˜=50%. This leads to stimulated emission in thin films and lasing in cylindrical μ cavities. The seeming contradiction of a degenerate ground-state polymer with high η is explained by the lowest excited-state ordering. © 1999 The American Physical Society.

DOI： 10.1103/PhysRevLett.82.4058

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

Polymerization and polymer properties of 1-phenyl-2-[4-(triphenylsilyl)phenyl] acetylene (pPh(3)SiDPA) and 1-phenyl-2-[4-(triisopropylsilyl)phenyl] acetylene (piPr(3)SiDPA), which have very bulky silyl groups, were examined. These monomers polymerized in good yields in the presence of TaCl5-based catalysts. The highest weight-average molecular weights of poly(pPh(3)SiDPA) and poly(piPr(3)SiDPA) reached about 1 x 10(6) and 4.8 x 106, respectively. The polymers were yellow to orange-colored solids which were soluble in toluene, chloroform, etc., and provided free-standing films by solution casting. The onset temperatures of weight loss of poly(pPh(3)SiDPA) and poly(piPr(3)SiDPA) in TGA in air were 430 and 270 degrees C, respectively. The oxygen permeability coefficients of poly(pPh(3)SiDPA) and poly(piPr(3)SiDPA) at 25 degrees C were 3.8 and 20 barrers, respectively, and relatively small. (C) 1998 John Wiley & Sons, Inc.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ACS  

Polymerization of [RhCl-(nbd)]2-Et3N yielded polyacetylenes having azobenzene moieties [poly(3-EAB) and poly(4-EAB)]. Poly(3-EAB) has high molecular weight up to 4.9×105 and dissolved in common organic solvents to give free-standing film by solution casting. Trans-cis photoisomerization of azobenzene moieties in the polymer took place by UV irradiation.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN J APPLIED PHYSICS  

Photoluminescence (PL) and electroluminescence (EL) in polymer mixture of blue emissive poly(1-hexyl-2-phenylacetylene) (PHxPA) and green emissive paly(1-phenyl-2-p-n-butylphenylacetylene) (PDPA-nBu) were studied. Both PL and EL in the polymer mixture change from blue to green by the addition of a small amount of PDPA-nBu into PHxPA. This fact has been interpreted as a result of energy transfer from the larger band eap PHxPA to the smaller band gap PDPA-nBu. PL and EL in the polymer mixture are found to be deconvoluted into PL1 and PL2 peaks originating from PDPA-nBu and PHxPA, respectively. PL1 of PDPA-nBu shifts to a higher energy upon introduction of PHxPA, while PL2 of PHxPA also shifts to a higher energy by adding a small amount of PDPA-nBu. From this change in luminescence, molecular conformation at the excited state in the mixture is interpreted to be distorted, depending on the molar ratio of PDPA-nBu and PHxPA. A similar change in PL and EL spectra with molar ratio implies that in this mixture the energy relaxation process is nearly the same for both the cases and does not strongly depend on whether the excited state is produced by photoexcitation or charge injection.

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Intense photoluminescence (PL) is observed in di-substituted polyacetylene derivatives even though solitonic mid-gap absorption is observed upon doping, contrary to non-substituted trans-polyacetylene and mono-substituted polyacetylene in which strong PL is not observed. Intense green and blue electroluminescence (EL) is realized utilizing poly(diphenylacetylene) derivatives and poly(1-alkyl-2-phenylacetylene) derivatives, respectively. Greenish-blue emission is also observed in poly(1-chloro-2-phenylacetylene) derivatives. The dependence of wavelength and intensity of PL and EL on the molecular structure of substituents is clarified in detail. The effects of molecular alignment and layer structure on the EL characteristics are also discussed. Upon intense light excitation, remarkable spectral narrowing due to stimulated emission is also observed in these di-substituted polyacetylene derivatives. (C) 1997 Elsevier Science S.A.

DOI： 10.1016/S0379-6779(98)80042-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC APPLIED PHYSICS  

We studied spontaneous and stimulated optical emission in films of di-substituted trans-polyacetylene (t-PA). We found that di-substitution of t-PA drastically changes the polymer optical emission properties, so that photo-generation of exciton and photoluminescence (PL) quantum yields become much higher than those measured in unsubstituted and mono-substituted t-PA. The strong PL is accompanied by high optical gain and emission spectral narrowing at high excitation intensities; the emission spectrum changes from a broad PL band of 100 nm at low intensities to a narrow stimulated emission band of similar to 8 nm at high intensities. These properties show that di-substituted t-PA films can be good candidates for laser medium in the green and blue spectral ranges.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN J APPLIED PHYSICS  

Intense green photoluminescence (PL) in the wavelength range of 520 to 540nm was observed in many poly(diphenylacetylene) (PDPA) derivatives. The band gap energy and the highest occupied molecular orbital (HOMO) energy of these polymers were estimated to range from 2.6 to 2.7 eV and -5.6 to -5.9eV depending on the substituent. Green electroluminescence (EL) was observed from EL devices fabricated utilizing these polymers. Among these PDPA derivatives, poly(1-phenyl-2-m-(trimethylsilyl)phenylacetylene) (PDPA-mSiMe(3)) with the smallest band gap energy exhibited the weakest PL and EL of longest wavelength. Polymers with bulkier and/or longer substituents exhibited stronger PL and EL. The results are interpreted in terms of a steric hindrance effect and the interchain interaction depending on the molecular structure of the substituents. In addition, upon electrochemical doping, these light emissive polyacetylene derivatives exhibited evolution of new single midgap absorption suggesting formation of solitons.

DOI： 10.1143/JJAP.36.3740

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Unique characteristics such as quenching of photoluminescence and improvement of photovoltaic effect were observed in donor polymeracceptor polymer composites, PAT6-CNPPV system and PDPATPSi-CNPPV system. Electronic energy structures of these polymers were determined and these characteristics are interpreted in terms of photoinduced charge transfer between donor polymer (PAT6 and PDPATPSi) and acceptor polymer (CNPPV) and formation of fractal network.

DOI： 10.1016/S0379-6779(97)80251-2

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC APPLIED PHYSICS  

Intense photoluminescence (PL) was observed in soluble disubstituted polyacetylenes such as poly(1-phenyl-2-p-adamantylphenyl acetylene (PDPA-Ad) at 530 nm, poly(1-phenyl-2-p-triphenylsilylphenyl acetylene) (PDPA-TPSi) at 530 nm and poly(1-hexyl-2-phenyl acetylene) (PHxPA) at 455 nm, although they are considered to be derivatives of trans-polyacetylene. In monosubstituted acetylene polymers such as poly(o-trimethylsilylphenyl acetylene) (PTMSiPA), PL was negligible. Green and blue light emissions were observed from an electroluminescent (EL) device having soluble poly(diphenyl acetylene) (PDPA) derivatives (PDPA-Ad and PDPA-TPSi) and PHxPA as emission layers, respectively. EL emission is clearly observable under normal room illumination conditions. The electronic energy structures of the disubstituted PA derivatives are also discussed to interpret PL and EL characteristics.

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

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Other Link： http://id.nii.ac.jp/1450/00007610/

Language：Japanese   Publisher：Japanese Society for Engineering Education  

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (other)  

Optical resolution membranes can separate mixtures of both enantiomers. The study is very challenging and fundamental and also applicable for production of medicine. © 2008, The Society of Polymer Science, Japan. All rights reserved.

DOI： 10.1295/kobunshi.57.898

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (other)   Publisher：電気化学会  

DOI： 10.5796/electrochemistry.75.834

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Other Link： https://jlc.jst.go.jp/DN/JALC/00300958919?from=CiNii

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Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：ELSEVIER SCI LTD  

Because of their unique structures and properties, pi-conjugated polymers have attracted the attention of scientists and engineers. The authors have studied the synthesis of two kinds of pi-conjugated poly(aromatic acetylene)s, i.e. poly(arylacetylene)s and poly(aryleneethynylene)s with the aim of obtaining new polymers having novel functions or higher performances. This review mainly concerns the authors' results, as follows: first, we describe the synthesis and properties of achiral poly (aryl acetylene) s, containing trimethylsilyl groups, oligodimethylsiloxanyl groups, dendritic groups, and glavinoxyl groups, for application as oxygen permselective, membrane materials. Their self-membrane-forming abilities and high oxygen permeabilities are presented. Second, the synthesis by asymmetric-induced polymerization of chiral poly(arylacetylene)s having both a main-chain chirality and chiral pendant groups and their application as optical resolution membranes are described. Third, two new synthetic methods for preparing chiral helical poly (phenyl acetylene) s without the coexistence of any other chiral moieties are presented. One is helix-sense-selective addition polymerization and the other is in situ removal of chiral pendant groups from membranes of poly(arylacetylene)s that also contain a main-chain chirality. The chiral helical poly(arylacetylene)s were tested as optical resolution membranes. The chiral and achiral poly(arylacetylene)s were synthesized by addition polymerization using metathesis catalysts or rhodium complexes. Finally, the synthesis of regiospecific poly(aryleneethynylene)s bearing stable radicals by the polycondensation of bromoethynylanthracene derivatives using a Pd(0) complex is described. The magnetization and the static magnetic susceptibility of the polyradicals are explained. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2006.04.047

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：高分子刊行会  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：The Society of Polymer Science, Japan  

DOI： 10.1295/kobunshi.53.946

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：高分子刊行会  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：化学工業社  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER CHEMICAL SOC  

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DOI： 10.1016/S0379-6779(00)00680-9

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER CHEMICAL SOC  

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

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