研究者詳細 - 山崎　慎一

論文 - 山崎　慎一

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Poly[2,6-(1,4-phenylene)-benzobisimidazole] Nanofiber Networks 査読

Jin Gong, Tetsuya Uchida, Shinichi Yamazaki, Kunio Kimura

MACROMOLECULAR CHEMISTRY AND PHYSICS 211 ( 20 ) 2226 - 2232 2010年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：WILEY-V C H VERLAG GMBH

The preparation of poly[2,6-(1,4-phenylene)-benzobisimidazole] (PPBI) nanofibers was examined using the crystallization of oligomers during isothermal polymerization of self-polymerizable 2-(1,4-carbophenoxyphenyl)-5,6-diaminobenzimidazole. The polymerization was carried out at 350 degrees C at a concentration of 1w-t.-% for 6 h in three kinds of solvent. The solvent influenced the morphology of PPBI precipitates significantly, and PPBI nanofiber networks were successfully formed in DBT, of which the width ranged from 30 to 110 nm. Molecules were aligned along the long axis of nanofibers. A fibrillar morphology with molecular orientation is ideal for high performance materials such as reinforcements, non-woven fabrics and so on. The nanofiber networks exhibit the highest thermal stability.

DOI： 10.1002/macp.201000306

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Thermally Induced Solid-State Synthesis of Fluorine-Containing Poly(ether oxadiazole) 査読

Yuka Maruyama, Yukihiko Maeda, Kanji Wakabayashi, Shinichi Yamazaki, Kunio Kimura

JOURNAL OF APPLIED POLYMER SCIENCE 118 ( 1 ) 91 - 98 2010年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：JOHN WILEY & SONS INC

Synthesis of poly[oxy-(2,3,5,6-tetrafluoro-1,4-phenylene)-(1,3,4-oxadiazol-2-yl)-1,4-phenylene] (F-PEOz) was examined by nucleophilic aromatic substitution reaction of 2-(4-hydroxyphenyl)-5-pentafluorophenyl-1,3,4-oxadiazole (HPOz). Only low molecular weight F-PEOz or crosslinked insoluble polymers were obtained by the solution polymerization with bases. In contrast, thermally induced solid-state polymerization of HPOz potassium salts at 180 degrees C for 1 h gave fully soluble F-PEOz with the yield of 84% and its reduced viscosity was 0.66 dL The longer polymerization time gave insoluble polymers due to the crosslinking reaction even in solid state. The solid-state polymerization did not undergo topochemically and it proceeded in an amorphous state. The crosslinking reaction was slightly inhibited by the solid-state polymerization. F-PEOz exhibited excellent solubility, high T(g) of 246 degrees C and good thermal stability. (c) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 91-98, 2010

DOI： 10.1002/app.32391

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Poly(2,5-benzimidazole) nanofibers prepared by reaction-induced crystallization 査読

Kazuya Kimura, Jin Gong, Shin-ichiro Kohama, Shinichi Yamazaki, Tetsuya Uchida, Kunio Kimura

POLYMER JOURNAL 42 ( 5 ) 375 - 382 2010年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：NATURE PUBLISHING GROUP

Morphological control of poly(2,5-benzimidazole) (PBI) was examined by reaction-induced phase separation of oligomers during polymerization to prepare nanofibers. Three monomers, 3,4-diaminobenzoic acid (DABA), 3,4-diacetoamidebenzoic acid (DAcBA) and phenyl 3,4-diaminobenzoate (PDAB), were used to synthesize PBI. Polymerizations were carried out at 350 degrees C in a mixture of dibenzyltoluene isomers. Polymerization of DABA yielded spheres with plate-like crystals on their surface. Polymerization of DAcBA yielded almost no precipitates because of the high solubility of DAcBA oligomers. By contrast, polymerization of PDAB yielded aggregates of PBI nanofibers (of which the average diameter was similar to 60 nm), which resembled nonwoven fabrics. These fibers were formed by precipitation of (2,5-benzimidazole) oligomers and their subsequent polymerization into a developing crystal structure. The structure of the monomer significantly influenced the morphology of the PBI product, and PDAB was preferable for the preparation of PBI nanofibers. The temperature of 10% N-2 weight loss in these nanofibers was in the range of 634-644 degrees C and they were thermally stable. Polymer Journal (2010) 42, 375-382; doi:10.1038/pj.2010.20; published online 17 March 2010

DOI： 10.1038/pj.2010.20

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Formation and Morphology of “Shish-like” Fibril Crystals of Aliphatic Polyesters from the Sheared Melt 査読

Shinichi Yamazaki, Manabu Itoh, Takuya Oka, Kunio Kimura

European Polymer Journal 46 ( 1 ) 58 - 68 2010年1月

ポリエステル類のシシケバブ構造形成におけるエステル交換反応を介した絡み合い解消の影響招待

山崎慎一

Sen’i Gakkaishi 66 ( 7 ) 237 - 239 2010年

Direct Synthesis of Wholly Aromatic Polyamides by Using Reaction-Induced Crystallization 査読

Kazufumi Kobashi, Kentaro Kobayashi, Haruki Yasuda, Kentaro Arimachi, Testuya Uchida, Kanji Wakabayashi, Shinichi Yamazaki, Kunio Kimura

MACROMOLECULES 42 ( 16 ) 6128 - 6135 2009年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Direct synthesis of rigid-rod aromatic polyamides was studied without condensation reagents by using reaction-induced crystallization of oligomers during solution polymerization. Polymerizations of p-aminobenzoic acid were carried out in an aromatic solvent at a polymerization concentration of 20% at 350 degrees C. High molecular weight poly(p-benzamide) (PBA) was obtained in the form of plate-like crystals, and the highest molecular weight was 11.6 x 10(3). In this polymerization, the oligomers were formed in the solution by the condensation reaction with the elimination of water. When the molecular weight of oligomers exceeded the critical value, the oligomers were precipitated by crystallization via supersaturated state to form the plate-like crystals. The molecular weight increased by the polymerization between the oligomers on and in the crystals. Poly(p-phenylene isophthalamide) (PPIA) was also obtained in the form of plate-like crystals by the polymerization of p-phenylene diamine (PPDA) and isophthalic acid (IPA) under the same condition as that of PBA. These results exhibited the thermally direct synthesis of infusible aromatic polyamides. Sequential addition of monomers into this heterogeneous polymerization was examined to increase the molecular weight. In the step-growth polymerization, the addition of monomers into the homogeneous polymerization could not increase the molecular weight because it was determined by the extent of reaction and reshuffled by the transamidation reaction. However, the addition of PPDA and IPA during the polymerization resulted in the increase in the molecular weight of PPIA. This result gave possibly a novel procedure for the preparation of high molecular weight condensation-type polymers.

DOI： 10.1021/ma9009033

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Topological Mechanism of Nucleation of Cyclic Polyethylene

Shinichi Yamazaki, Shouichi Ida, Kunio Kimura

物性研究 92 ( 1 ) 47 - 50 2009年4月

球晶成長速度をプローブにした脂肪族ポリエステル類のエステル交換反応を介した絡み合い解消の可能性の検証査読

山崎慎一, 岡卓也, 木村邦生

高分子論文集 66 ( 10 ) 475 - 482 2009年

Preparation of Poly(4 '-oxy-4-biphenylcarbonyl) Needlelike Crystals with the Aid of Copolymerization 査読

Naomi Yoshida, Yasuhiro Kurihara, Shin-ichiro Kohama, Tetsuya Uchida, Shinichi Yamazaki, Kunio Kimura

MACROMOLECULES 41 ( 20 ) 7571 - 7578 2008年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Preparation of poly(4'-oxy-4-biphenylcarbonyl) (POBP) needlelike crystals was examined by using reaction-induced crystallization of oligomers during copolymerization of 4-(4-aceloxypheilyl)benzoic acid (APBA) and 4-acetoxybenzoic acid (ABA). Polymerizations were carried out in aromatic solvent at various ABA molar ratios in feed (chi(f)). When they chi(f) was 20-10 mol %, starlike aggregates of needlelike crystals and fibrillated slablike crystals were separately formed, exhibiting similar morphology to poly(4-oxybenzoyl) and POPB crystals. 4-(Oxyphenyl)benzoyl (OPB) homo-oligomers and co-oligomers rich in OPB moiety were more rapidly precipitated due to the lower solubility, and the slablike crystals were formed. Afterward, 4-oxybenzoyl (013) homo-oligomers and the co-oligomers rich in OB moiety were precipitated to form spindlelike crystals. The OPB homo-oligomers and the co-oligomers rich in OPB moiety were continuously crystallized on both crystals due to the high degree of supersaturation. and the spindlelike crystals grew to the needlelike crystals mainly comprised of POBP. Copolymerization of 4-(4-acetoxybenzoyloxy)benzoic acid and APBA at chi(f) of 10 mol % yielded the needlelike crystals without coexisting fibrillated slablike crystals. This result provides a new methodology for morphology control with the aid of copolymerization.

DOI： 10.1021/ma800029n

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Preparation of brush-like crystals of poly[2,6-(1,4-phenylene)-benzobisimidazole] 査読

Jin Gong, Shin-ichiro Kohama, Kazuya Kimura, Shinichi Yamazaki, Kunio Kimura

POLYMER 49 ( 18 ) 3928 - 3937 2008年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

Poly[2,6-(1,4-phenylene)-benzobisimidazole] (PPBI) crystals were prepared by using reaction-induced crystallization of oligomers during solution polymerization of 1,2,4,5-tetraaminobenzene and diphenyl terephthalate. Polymerizations were carried out at a monomer concentration of 4.3 x 10(-2) mol L-1 at 350 degrees C for 6 h. Brush-like PPBI crystals were obtained in a mixture of structural isomers of dibenzyltoluene, in which many needle-like crystals came out vertically from the surface of the ribbon-like crystals. Average width and thickness of the ribbon-like crystals were 0.75 mu m and 0.11 mu m, respectively. And average length and diameter of the needle-like crystals were 0.36 mu m and 50 nm, respectively. The brush-like crystals possessed high crystallinity and exhibited good thermal resistance. The ribbon-like crystals were formed by the crystallization of imidazole oligomers at an initial stage of polymerization, and then the needle-like crystals grew from the surface of the ribbon-like crystals. Polymerization occurred on the crystals when the oligomers were crystallized, leading to the high molecular weight PPBI crystals. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2008.07.011

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Fabrication of rod-like crystals of poly(p-oxycinnamoyl) by hydrodynamically induced crystallization during solution polymerization 査読

Shin-ichiro Kohama, Mayuko Muraoka, Shinichi Yamazaki, Kunio Kimura

SEN-I GAKKAISHI 64 ( 8 ) 220 - 223 2008年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SOC FIBER SCIENCE TECHNOLOGY

Microspheres of poly(p-oxycinnamoyl) (POC) were obtained by the polymerization of (E)-4-acetoxycinnamic acid in aromatic solvent at 320 degrees C and a concentration of 1.5% without stirring via liquid-liquid phase separation of oligomers. In contrast to this, rod-like crystals were formed under shearing with more than 700 rpm. The obtained rod-like crystals were 10-15 mu m in length and 1.0-1.5 mu m in width having many thorns on the surface. The critical stirring speed for the onset of Taylor vortices was in agreement with 700 rpm and the crystallization of oligomers was hydrodynamically induced by the generation of Taylor vortices affording the rod-like crystals. Stirring influenced the morphology of POC significantly and this work provided a new procedure for the fabrication of fine fibers of intractable aromatic polymers.

DOI： 10.2115/fiber.64.220

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Preparation of poly(4-phthalimide) nanoribbon by reaction-induced crystallization 査読

Kanji Wakabayashi, Tetsuya Uchida, Shinichi Yamazaki, Kunio Kimura

MACROMOLECULES 41 ( 13 ) 4607 - 4614 2008年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

The morphology of poly(4-phthalimide) (PPI) crystals was examined by using reaction-induced crystallization of oligomers during solution polymerization. Polymerizations of alkyl 4-aminophthalates such as I-ethyl 4-aminophthalate (1EAP), 2-ethyl 4-aminophthalate, 1-hexyl 4-aminophthalate, and 2-hexyl 4-aminophthalate were carried out at 330 degrees C in a mixture of isomers of dibenzyltoluene without stirring. Nanoscale PPI ribbons having smooth surface were formed by the polymerizations of these monomers. The ribbons prepared from 1EAP at a concentration of 2.0% for 24 h were averagely 12 mu m in length, 150 urn in width, and 8 nm in thickness, in which the molecular chains aligned along the long axis of the ribbon. The phase-separated oligomers were fully cyclized imide oligomers, and this is of great importance for the formation of the ribbon. The obtained ribbons possessed high crystallinity and exhibited excellent thermal stability.

DOI： 10.1021/ma800874w

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Composition control of aromatic copolyesters by shearing 査読

Kunio Kimura, Toshimitsu Ichimori, Kanji Wakabayashi, Shin-ichiro Kohama, Shinichi Yamazaki

MACROMOLECULES 41 ( 12 ) 4193 - 4199 2008年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Composition control of copolyester was examined by using hydrodynamically induced phase separation, during solution polymerization, of p-acetoxybenzoic acid and m-acetoxybenzoic acid (m-ABA). Polymerizations were carried out in liquid paraffin at 1.0% of concentration under shear flow. The polymers were obtained as precipitates formed via phase separation of oligomers and the subsequent polymerization in the precipitates. When the feed ratio of m-ABA (chi(f)) was 20 mol %, the molar ratio of m-oxybenzoyl moiety in the precipitated polymers (chi(p)) was 5.3, 3.1, and 2.3 mol % at a shear rate (gamma) of 0, 147, and 489 s(-1), respectively. The values of chi(p) were much lower than those of chi(f), and shear flow lowered the value of chi(p); thus, controlling shear flow influenced both the reaction rate of the monomers and the miscibility of the oligomers. It especially enhanced the difference on the miscibility between homo-oligomers and co-oligomers. This change in the miscibility by shear flow brought about the more rapid precipitation of homo-oligomers than co-oligomers, leading to the selective formation of poly(p-oxybenzoyl).

DOI： 10.1021/ma800529d

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Improvement of adhesion and long-term adhesive reliability of liquid crystalline polyester film by plasma treatment 査読

Yasuhiro Kurihara, Hiroyuki Ohata, Masahiko Kawaguchi, Shinichi Yamazaki, Kunio Kimura

JOURNAL OF APPLIED POLYMER SCIENCE 108 ( 1 ) 85 - 92 2008年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：JOHN WILEY & SONS INC

Surface modification of thermotropic liquid crystalline aromatic polyester (LCP) films was examined by low-pressure plasma treatment to improve initial adhesion and long-term adhesive reliability between the LCP film and an epoxy bonding sheet for printed circuit boards. Plasma irradiation was carried out in various plasma gases with different plasma modes as reactive-ion-etching (RIE), direct-plasma (DP) with pressures ranging from 4.0 to 26.6 Pa. Although the initial adhesion of the DP-treated film increased, the long-term adhesive reliability estimated by pressure cooker test (PCT) decreased with decreasing the plasma gas pressure in every gas. The higher concentration of the generated polar groups such as phenolic hydroxyl group and carboxyl group enhanced the initial adhesion by the increase in the chemical interaction; however, it damaged the long-term adhesive reliability due to the acceleration of the penetration of water molecules into the interface. The large surface roughness was effective to enhance the initial adhesion and the long-term adhesive reliability. The RIE-treatment generated the polar groups and the larger surface roughness than the DP-treatment. The RIE-treatment in the O-2 atmosphere at the gas pressure of 13.3 Pa was the best plasma condition for both the initial adhesion and the long-term adhesive reliability. (C) 2007 Wiley Periodicals, Inc.

DOI： 10.1002/app.27537

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Morphology control of poly(2,2’-phenylene-5,5’-bibenzimidazole) by reaction-induced crystallization during polymerization 査読

Shin-ichiro Kohama, Jin Gong, Kazuya Kimura, Shinichi Yamazaki, Tetsuya Uchida, Kaoru Shimamura, Kunio Kimura

Polymer 49 ( 7 ) 1783 - 1791 2008年4月

Fluorinated poly(aryl thioether)s and poly(aryl sulfone)s derived from 2,3,4,5,6-pentafluorobenzoic acid 査読

Shunsuke Masaki, Natsuko Sato, Ai Nishichi, Shinichi Yamazaki, Kunio Kimura

JOURNAL OF APPLIED POLYMER SCIENCE 108 ( 1 ) 498 - 503 2008年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：JOHN WILEY & SONS INC

Poly(aryl thioether)s (F-PTEs) containing 2,3,5,6-tetrafluoro-1,4-phenylene moiety and polar moiety, such as 1,3,4-ozadiazole, ether ketone, and amide groups, were synthesized by nucleophilic aromatic substitution reaction of aryl fluorides and 4,4'-thiobisbenzenthiol. F-PTEs were amorphous with good thermal properties including high glass transition temperature (T-g) and thermal stability, solubility, and hydrophobicity. F-PTEs were transformed into poly(aryl sulfone)s (F-PSs) by the oxidation reaction with hydrogen peroxide in acetic acid. Because of the sulfone group, the T(g)s of the F-PSs were 30-40 degrees C higher than those of the corresponding F-PTEs. F-PSs maintained solubility in polar aprotic solvents and exhibited hydrophobicity in spite of the content of polar sulfone groups due to the highly substituted fluorine atoms. These F-PTEs and F-PSs were a new class of high-performance polymers. (C) 2008 Wiley Periodicals, Inc.

DOI： 10.1002/app.27347

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Dimer effect on fractional polycondensation of poly(p-oxybenzoyl) 査読

Kunio Kimura, Yasuo Shimizu, Toshimitsu Ichimori, Shin-Ichiro Kohama, Shinichi Yamazaki, Yuhiko Yamashita

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY 46 ( 5 ) 1598 - 1606 2008年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：JOHN WILEY & SONS INC

Selective preparation of poly(p-oxybenzoyl) (POB) crystals was examined from the viewpoint of a dimer effect on fractional polycondensation. Four different copolymerization systems were chosen as the combinations of p-acetoxybenzoic acid (p-ABA), m-acetoxybenzoic acid (m-ABA), and their dimers. The crystals obtained from the copolymerization of the dimer of p-ABA (p-ABAD) and m-ABA contained only 3.1 mol % of m-oxybenzoyl moiety even at high content of m-oxybenzoyl moiety in feed (chi(f)) of 40 mol %. p-Oxybenzoyl homo-oligomers were more rapidly formed from p-ABAD in the solution than from p-ABA, and they were crystallized to form the crystals with segregating co-oligomers. While co-oligomers containing more m-oxybenzoyl moiety were formed in the solution, afterward they were unable to be phase-separated because of higher miscibility. The further polycondensation proceeded in the precipitated crystal, and finally the POB crystal was selectively formed. Lower polymerization temperature and concentration enhanced the fractionability, and the POB crystals containing less than 1 mol % m-oxybenzoyl moiety were prepared at chi(f) of 30 mol %, 270 degrees C, and a concentration of 0.5%. The dimer effect on the fractional polycondensation was clearly observed. (C) 2008 Wiley Periodicals, Inc.

DOI： 10.1002/pola.22496

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Nonstoichiometric Synthesis of Poly(4,4’-oxydiphenylene pyromelliteimide) by Reaction-Induced Crystallization of Oligomers 査読

Kanji Wakabayashi, Shin-ichiro Kohama, Shinichi Yamazaki, Kunio Kimura

Macromolecules 41 ( 4 ) 1168 - 1174 2008年2月

Improvement of Adhesion Between Liquid Crystalline Polyester Films by Plasma Treatment 査読

Yasuhiro Kurihara, Hiroyuki Ohata, Masahiko Kawaguchi, Shinichi Yamazaki, Kunio Kimura

JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY 22 ( 16 ) 1985 - 2002 2008年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：BRILL ACADEMIC PUBLISHERS

Surface modification of thermotropic liquid crystalline aromatic polyester (LCP) films was carried out by low-pressure plasma treatment to improve the initial adhesion as well as the long-term adhesion reliability, a measure of durability between the LCP films used as substrates for printed circuit boards. Plasma irradiation was carried out in various plasma gases with different plasma modes such as reactive-ion-etching, and direct-plasma (DP) with pressures ranging from 6.7 Pa to 26.6 Pa. The introduction of polar groups on the film surface such as phenolic hydroxyl groups and carboxyl groups enhanced the initial adhesion by increased chemical interaction. However, if the concentration of polar groups became too high, the long-term adhesion reliability estimated by the pressure cooker test was degraded due to the acceleration of the penetration of water molecules into the interface. A large surface roughness was also effective in preventing the decrease in the long-term adhesion reliability. However, too much increase in surface roughness decreases the long-term adhesion reliability. The DP-treatment in the O(2) atmosphere at a gas pressure of 6.7 Pa was found to be the best plasma condition for both the initial adhesion as well as the long-term adhesion reliability between the LCP films. (C) Koninklijke Brill NV, Leiden, 2008

DOI： 10.1163/156856108X331751

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Fabrication of nanoribbon of high-performance polyimide

K. Wakabayashi, S. Yamazaki, T. Uchida, K. Kimura

American Chemical Society, Polymer Preprints, Division of Polymer Chemistry 49 ( 1 ) 331 - 332 2008年

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