- 著者
- Kawabata Kohsuke Goto Hiromasa
- 出版者
- Royal Society of Chemistry
- 雑誌
- Journal of materials chemistry (ISSN:09599428)
- 巻号頁・発行日
- vol.22, no.44, pp.23514-23524, 2012-09
- 被引用文献数
- 20 4
A series of axially chiral 1,1-binaphthyl–thiophene copolymers were synthesized by Migita–Kosugi–Stille polycondensation and electrochemical polymerization. The polymers exhibit circular dichroism not only in the ultraviolet region but also in the visible region, both in solution and film states. Optical and electrochemical properties of the polymers are in good agreement with theoretical results obtained by density functional theory calculations. Although effective conjugation of the polymers was cleaved at the orthogonally oriented two naphthalene rings in the 1,1-binaphthyl unit, the electrochemically synthesized polymer film shows good electrochemical redox behavior with repeatable changes in optical absorption and circular dichroism. The changes in circular dichroism may reflect a change in the dihedral angle of the binaphthyl unit caused by reorientation of conjugated main chains between oxidized and neutral states.
- 著者
- Goto Hiromasa Yokoo Atsushi
- 出版者
- Taylor and Francis Group
- 雑誌
- Designed monomers and polymers (ISSN:1385772X)
- 巻号頁・発行日
- vol.15, no.6, pp.601-608, 2012-07
- 被引用文献数
- 4 3
We report preparation of polyaniline (PANI) with radicals on the N-positions. Chirality of a PANI having optically active substituent is retained even upon oxidation by m-chloroperoxybenzoic acid in chloroform to generate spin species. Electron spin resonance and circular dichroism spectroscopy measurements suggest that the chiral paramagnetic properties of PANIs are derived from the combination of chiral side chains and oxyradicals in the structure of the polymer. This report focuses on a new synthetic approach for obtaining magneto-optically active polyanilines.
- 著者
- Kawashima Hirotsugu Shinotsuka Masako Nakano Mutsuko Goto Hiromasa
- 出版者
- Springer US
- 雑誌
- Journal of coatings technology and research (ISSN:15470091)
- 巻号頁・発行日
- vol.9, no.4, pp.467-474, 2012-07
- 被引用文献数
- 8 1
Conductive polymers have been studied extensively because of their attractive physical properties, such as conductivity, luminescent performance, and dielectric property. Poly(3,4-ethylenedioxythiophene) (PEDOT) is one of the most employed conductive polymers for applications, such as a buffer layer of organic electroluminescent devices, due to its high conductivity and electrical stability. In this study, we fabricated a conductive paper coated with PEDOT by direct polymerization onto a paper sheet. The conductive paper exhibited the electrical conductivity of 1.8 S/cm. Scanning electron microscopy images of the conductive paper showed two structures: thin polymer membranes attached to cellulose fibers at the surfaces, and thick polymer sheets extended through the void spaces between the fibers in the inner layers. Consequently, strong interactions between the PEDOT and the cellulose fibers enhanced mechanical properties of the conductive paper. Electron probe X-ray microanalysis (EPMA) revealed distribution elemental maps of carbon, oxygen, sulfur, chlorine, and iron on the conductive paper.Journal of Coatings Technology and Research Journal of Coatings Technology and Research LookInsideShareShare this content on Facebook Share this content on Twitter Share this content on LinkedInWithin this Article Introduction Experimental section Results and discussion Conclusions References ReferencesOther actions Export citations Register for Journal Updates About This Journal Reprints and Permissions
- 著者
- Hayashi Hitoshi Wang Aohan Kawabata Kohsuke Goto Hiromasa
- 出版者
- Elsevier
- 雑誌
- Materials chemistry and physics (ISSN:02540584)
- 巻号頁・発行日
- vol.137, no.3, pp.816-824, 2013-01
- 被引用文献数
- 11
A series of chiral three-ring type compounds with rigid shape was employed as chiral inducers for induction of chiral cholesteric liquid crystal (cholesteric LC) from achiral nematic LC. Helical twisting power of the chiral compounds was estimated with the Cano wedge method. Cholesteric LC electrolyte solution was prepared by adding the chiral compounds. Subsequently, polymerization in the cholesteric LC was carried out to produce chiroptically active polymer films. This method is different from conventional methods for synthesizing chiral polymers because neither chiral monomers nor asymmetric catalysts are employed. Surface structure and optical properties of the polymer thus prepared were examined.