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Masayuki Chokai, Yuta Nabae, Shigeki Kuroki, Teruaki Hayakawa, Masa-ak ...
2011 年 24 巻 3 号 p.
241-246
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
Carbon-based catalysts, non-precious metal catalysts for the oxygen reduction reaction (ORR), were prepared from polyimides (PI) with iron species. Nano spherical PI with iron composite was used as starting materials. Nano spherical carbon-based catalysts with diameter of 200-300 nm could be obtained by carbonization of the nano spherical starting materials. The obtained nano-sized catalyst showed higher ORR activity and higher four electron reduction selectivity as compared pulverized catalysts prepared from bulk sample.
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Shinsukei Inoue, Katuhiro Sakamoto, Satoru Nanba
2011 年 24 巻 3 号 p.
247-249
発行日: 2011/06/21
公開日: 2011/08/04
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Masaki OKazaki, Ken-ichi Fukukawa, Yoshihiro Sakata, Tatsuhiro Urakami ...
2011 年 24 巻 3 号 p.
251-254
発行日: 2011/06/21
公開日: 2011/08/04
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Ken-ichi Fukukawa, Masaki Okazaki, Yoshihiro Sakata, Tatsuhiro Urakami ...
2011 年 24 巻 3 号 p.
255-258
発行日: 2011/06/21
公開日: 2011/08/04
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Mitsuhiro Suwa, Takanori Fujikawa, Toru Okazaki, Hiroshi Araki
2011 年 24 巻 3 号 p.
259-261
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
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Mihoko Hirai, Masahiro Tada, Yoshihito Akiyama, Kazuhiro Koga
2011 年 24 巻 3 号 p.
263-266
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
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Shinji Fukuda, Ken Amagai, Satoru Kanke, Katsuya Sakayori
2011 年 24 巻 3 号 p.
267-268
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
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Aya Kasahara, Akio Takahashi, Toshiyuki Oyama
2011 年 24 巻 3 号 p.
269-272
発行日: 2011/06/21
公開日: 2011/08/04
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Yuta Saito, Tomoya Higashihara, Mitsuru Ueda
2011 年 24 巻 3 号 p.
273-276
発行日: 2011/06/21
公開日: 2011/08/04
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Kimiya Murakami, Shinji Ando
2011 年 24 巻 3 号 p.
277-282
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
For controlling the optical and thermal properties of photo-sensitive benzophenone (BP)- containing polyimides (PIs), an attempt was made to fix the dense polymer chain packing induced by high pressure using intermolecular crosslinking reactions. The effects of temperature and pressure during UV irradiation on the reaction rates of photo-crosslinking and refractive indices were evaluated. After UV irradiation at ambient temperature and pressure, refractive indices of the PIs increased due to the densification of chain packing. The degree of crosslinking was further increased with increasing the irradiation temperature. The PI films irradiated at 400 MPa exhibited higher refractive indices than those irradiated at 0.1 MPa, despite the nearly identical reaction rates. The fluorescence intensities of the PIs irradiated at 400 MPa showed smaller dependence on the pressure than those irradiated at 0.1 MPa, which indicates that the dense chain packing formed under high pressures was partially and effectively fixed by UV irradiation. The increase in refractive indices of the PIs irradiated at elevated pressures is attributable to the densification of aggregation structures, which was controllable by pressure under UV irradiation.
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Yuki Shirai, Takehiro Kawauchi, Tsutomu Takeichi, Hiroshi Itatani
2011 年 24 巻 3 号 p.
283-286
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
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Junichi Ishii, Hideyuki Yokotsuka, Takayuki Saito, Masatoshi Hasegawa
2011 年 24 巻 3 号 p.
287-291
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
A phosphorus (P)-containing diamine was synthesized and used as a comonomer at a minor fraction to improve insufficient non-flammability of a poly(ester imide) system as a promising candidate of base film materials in flexible printed circuit boards (FPC). The P-modified PEsI copolymer film displayed the highest level of non-flammability (UL-94, V-0) comparable to commercially available conventional aromatic PI films in addition to original excellent properties, i.e., a very high T
g, a low linear coefficient of thermal expansion (15.7 ppm/K) close to copper foils, a low water absorption (0.54 %), a low linear coefficient of humidity expansion (5.53 ppm/RH%), and sufficient toughness (elongation at break = ca. 40%). This approach was also attempted for a very flammable low-modulus PI system for aiming at an application as a coating-type cover layer material in FPC.
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Yingwei Liu, Hiroki Komatsuzaki, Ryuta Ikoma, Yasuhiro Nishioka
2011 年 24 巻 3 号 p.
293-298
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
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Xu Lin, Takashi Hattori, Shiki Yagai, Akihide Kitamura, Takashi Karats ...
2011 年 24 巻 3 号 p.
299-303
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
We report the novel oligomer host material derived from 3,6-carbazole and diphenylsilane. Through the σ-Si structure, tetraphenylsilane moieties effectively interrupt the extending of &pai;-conjugation, triplet energy level of the host material increased to 2.95 eV successfully in oligomer chain. In addition, this oligomer host material exhibited high glass transition temperature (Tg = 119 °C) and matching HOMO (-5.57 eV) and LUMO (-2.12 eV) level with both electrodes. Employing the host material doped with green and blue-emitters as the emissive layer, we fabricated light-emitting diodes by solution processing, the maximum luminance for blue device was 454 cd/m
2.
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Yusuke Washino, Kazuma Tsuboi, Tsuyoshi Michinobu
2011 年 24 巻 3 号 p.
305-309
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
Polymeric electro-optic materials were prepared by simple heating of a mixed thin film of TCNQ polyester (P1) and dialkyne molecule (1) to 140 °C under electric poling. A thermal addition reaction between electron-rich alkynes and TCNQ moieties allowed for donor-acceptor chromophores and, at the same time, cross-linking in the polymer (P2) films. Although it took around 13 h to complete the reaction, the electro-optic coefficient (d
eff) showed the maximum value of 0.609 pm V
-1 after 2.5 h. This was probably achieved by the sufficient chromophore formation and the effective fixation of the dipolar orientation. A comparison to a soluble model polymer (P3) clearly demonstrated a positive effect of the cross-linking. The desired polymer structure was confirmed by electrochemical redox potentials and a high thermal stability.
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Hiroyuki Fujita, Yupin Yuan, Tsuyoshi Michinobu
2011 年 24 巻 3 号 p.
311-315
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
Photovoltaic properties of a conventional bulk heterojunction organic solar cell composed of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) were investigated as a function of the addition amount of a p-type doping reagent, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F
4TCNQ). Addition of a small amount of F
4TCNQ to P3HT induced spectral changes with the appearance of low energy polaron bands, suggesting the efficient doping of the p-type semiconductor. The doping also resulted in the improved hole conduction, as revealed by current density-voltage (J-V) curves in the dark. A systematic study of the devices indicated that the soft doping with F
4TCNQ and the utilization of a hole-transporting PEDOT:PSS layer on an ITO electrode sometimes improve the short-circuit current density (J
SC) and fill factor (FF). In contrast, the hard doping always generates hole-trapping sites. Based on this knowledge, the device performances were successfully optimized.
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Michinori Nishikawa
2011 年 24 巻 3 号 p.
317-320
発行日: 2011/06/21
公開日: 2011/08/04
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We developed novel organic-solvent-soluble polyimide (PI) alignment films with a steroidal structure for liquid crystal display (LCD) televisions (TVs). The PIs can generate any desired pretilt angles between 3 - 90 °, which are needed to realize LCD-TVs such as twisted nematic, optically compensated bend, and vertical alignment LCD modes. The PIs also showed very stable pretilt angles, together with good electrical properties. The developed PI alignment films have been widely used for large screen size LCD-TVs with the display performance such as high contrast, fast response time, and wide viewing angle.
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Akito Kawanami, Katsuhiko Fujita
2011 年 24 巻 3 号 p.
321-324
発行日: 2011/06/21
公開日: 2011/08/04
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フリー
The evaporative spray deposition using ultradilute solution (ESDUS) technique enables layer-by-layer deposition of polymer semiconductors. In the present study we prepared inverted organic photovoltaic cells with stacked layer structure of mixture film of a polythiophene and a fullerene derivative (i-layer) and polythiophene film (p-layer) by ESDUS. The i-p stacked structure brought about significant improvement in the device performance probably due to the electron blocking at the polythiophene film.
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Yanhui Lou, Zhaokui Wang, Shigeki Naka, Hiroyuki Okada
2011 年 24 巻 3 号 p.
325-328
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
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Zhenbo Cao, Kou Yamada, Kousuke Tsuchiya, Kenji Ogino
2011 年 24 巻 3 号 p.
329-335
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー
The two succinates containing tetraphenyldiaminobiphenyl (TPD) or tetraphenylphenylenediamine (PDA) unit as a charge transporting moiety and dicyanovinylaniline unit as an electro-optical (EO) chromophore were prepared. Synthesized succinates (TPD-2DCVA, and PDA-2DCVA) show glass transition and form stable amorphous molecular glass at room temperature without a polymer binder or a plasticizer. TPD-2DCVA doped with 0.2 wt% of fullerene shows 28% of diffraction efficiency, and 110 cm
-1 of coupling gain at 55V/μm, while PDA-2DCVA shows no photorefractivity at room temperature probably due to the difficulty of orientation of EO moiety because of higher glass transition temperature. The diffraction efficiency of TPD-2DCVA significantly increased by the addition of 0.5 wt % of PDA-2DCVA, which might be due to the increase of trap density. Fast response, observed for TPD-2DCVA, was ascribed to the large photoconductivity.
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Tatsuo Mori, Yoshihisa Iida
2011 年 24 巻 3 号 p.
337-342
発行日: 2011/06/21
公開日: 2011/08/04
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We study the evaporation process by means of a single evaporation source putting in the mixture of two hole-transport materials(HTMs) for organic light-emitting diodes. In the case of the mixture of two HTMs with large difference, 120, of evaporation threshold temperature (Te), when evaporation temperature rises at a constant rate with time, the HTM with higher Te vaporizes after the HTM with lower Te vaporized. In the case of the mixture of TPD:α-NPD =1:1 with the difference of 50K, only a single evaporation curve is observed in the temperature region between the evaporation curve of only TPD and that of only α-NPD. The fabricated thin films using the mixture of TPD:α-NPD =1:1 under a constant temperature consist of TPD:α-NPD = 10:1. This is because the Te of TPD increases and that of α-NPD decreases.
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Win Tang, Wataru Saito, Kousuke Tsuchiya, Kenji Ogino
2011 年 24 巻 3 号 p.
343-344
発行日: 2011/06/21
公開日: 2011/08/04
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フリー
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Yoshihito Kunugi, Tatsuya Arai, Norihito Kobayashi, Hiroyuki Otsuki, T ...
2011 年 24 巻 3 号 p.
345-348
発行日: 2011/06/21
公開日: 2011/08/04
ジャーナル
フリー