研究者詳細 - 山崎　慎一

論文 - 山崎　慎一

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Synthesis and properties of fluorine-containing poly(aryl ether oxadiazole)s 査読

Natsuko Sato, Ken Tanaka, Shunsuke Masaki, Shinichi Yamazaki, Kunio Kimura, Al Nishichi

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY 45 ( 14 ) 2855 - 2866 2007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：JOHN WILEY & SONS INC

Fluorine-containing poly(aryl ether 1,3,4-ozadiazole)s were synthesized by the nucleophilic aromatic substitution reaction of 2,5-bis(2,3,4,5,6-pentafluorophenyl)-1,3,4-oxadiazole and various bisphenols in the presence of potassium carbonate. The polymerizations were carried out at 30 degrees C in 1-methyl-2-pyrrolidinone to avoid the gelation caused by a crosslinking reaction at para and ortho carbons to the 1,3,4-oxidiazole ring. The obtained polymers were all para-connected linear structures. The obtained fluorine-containing poly(aryl ether 1,3,4-ozadiazole)s showed excellent solubility and afforded tough, transparent films by the solution-casting method. They also exhibited a high glass transition temperature depending on the molecular structure, and the glass transition temperature could be controlled by the bisphenols in the range of 157-257 degrees C. They showed good thermal stability and excellent hydrophobicity due to the incorporation of the 2,3,5,6-tetrafluoro-1,4-phenylene moiety. (c) 2007 Wiley Periodicals, Inc.

DOI： 10.1002/pola.22041

Morphological architecture of poly(p-oxybenzoyl) by modification of oligomer end-group 査読

Kunio Kimura, Yasuhiro Kurihara, Hideki Omori, Shin-ichiro Kohama, Shinichi Yamazaki, Yuhiko Yamashita

POLYMER 48 ( 12 ) 3429 - 3436 2007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：ELSEVIER SCI LTD

Influence of oligomer end-group on morphology of poly(4-oxybenzoyl) (POB) was examined by polymerizations of 4-acyloxybenzoic acids having different acyl groups. Polymerizations of 4-propionyloxybenzoic acid, 4-hexanoyloxybenzoic acid, 4-octanoyloxybenzoic acid and 4-decanoyloxybenzoic acid in liquid paraffin at 320 degrees C yielded needle-like or pillar-like POB crystals via crystallization of oligomers. On the other hand, the polymerization of 4-perfluorooctanoyloxybenzoic acid (FOBA) afforded microspheres having needle-like crystals on the surfaces. At an initial stage in the polymerization, microspheres having smooth surface were formed via liquid-liquid phase separation of oligomers prepared from FOBA owing to the low miscibility of perfluorooctanoyl end-group. Thereby the phase-separation behaviour of oligomers changed from liquid-liquid phase separation to crystallization at a middle stage in the polymerization and then needle-like crystals were formed on the surface of the microspheres. Chemical structure of the oligomer end-group affected significantly the phase-separation behaviour of oligomers and ultimately the morphology of POB. (C) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2007.04.025

流動場結晶化における異形微粒子添加によるshish構造形成の促進

山崎慎一, 若林完爾, 水間健太, 木村邦生

岡山大学環境理工学部研究報告 12 ( 1 ) 157 - 160 2007年3月

記述言語：日本語出版者・発行元：岡山大学環境理工学部

We have shown that the shish was formed from the oriented melt composed of the elongated chains caused by dust particles within the melt via bundle typed nucleation under flow with low shear rate (γ=5s(-1)). This implies that dust particles effectively cause the elongation of chains within the melt. In this work, we observed the crystallization of polypropylene added with irregular shaped particles under shear flow by means of polarizing optical microscope. We prepared various shaped particles such as confetti-like, spherical and rock-like. We found that the size and asymmetric shape of additive particles play an important role for the acceleration of formation of shish.

結晶化処理を用いたポリブチレンテレフタレートの効果的鎖延長反応の開発

井原誠司, 城間弥, 山崎慎一, 木村邦生

岡山大学環境理工学部研究報告 12 ( 1 ) 167 - 171 2007年3月

記述言語：日本語出版者・発行元：岡山大学環境理工学部

Plastics are quite important materials for not only industrial usages but also our daily life. Many plastics are difficult to reuse because they are susceptible to UV, hydrolysis and so on leading to the reduction of molecular weight. Among them, poly (butylenes terephthalate) (PBT) is a valuable materials prepared by polycondensation reaction, and PBT has the same limitation to reuse. Hence, efficient chain extension reaction for recovered PBT has been needed to improve the properties damaged by chain scission. In this study, new chain extension reaction had been examined by using crystallization as pre-treatment. Isothermal crystallization at 161℃ concentrated the chain end-groups on the surface of the crystals, and chain extension reaction at 210℃, which was lower than the melting temperature of PBT, enhanced the molecular weight significantly compared with the reaction over the melting temperature. It concluded that the pre-treatment of crystallization was favorable for the efficient chain extension reaction and this result provided the new technology for the effective reuse of the plastics.

Fabrication of particles and crystals of poly(p-phenylene pyromelliteimide) and the study on crystal structure 査読

Kanji Wakabayashi, Tetsuya Uchida, Shinichi Yamazaki, Kunio Kimura, Kaoru Shimamura

MACROMOLECULES 40 ( 2 ) 239 - 246 2007年1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

Morphologies of poly(p-phenylene pyromelliteimide) (PPPI) were investigated by using phase separation during polymerization of pyromellitic dianhydride (PMDA) and p-phenylene diamine (PPDA). Polymerizations were carried out at 330 degrees C for 6 h. PPDA was added to the solution of PMDA in an aromatic solvent at various temperatures after PMDA was entirely dissolved. The morphology of the precipitates was drastically changed with the temperature of PPDA addition (Tad). When Tad was 240 degrees C, the fine particles were formed through the formation of droplets via liquid-liquid phase separation. On the contrary, when Tad was higher than 280 degrees C, the mixture of lozenge-shaped crystals and starlike aggregates of needlelike crystals were formed by the crystallization of oligomers. Tad influenced the degree of imidization of oligomers, resulting in the variation in the morphology of PPPI. Crystal structure and molecular chain orientation of the lozenge-shaped crystals were also investigated by high-resolution transmission electron microscope.

DOI： 10.1021/ma062032y

Morphology control of various aromatic polyimides by using phase separation during polymerization 査読

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

POLYMER 48 ( 2 ) 458 - 466 2007年1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

Morphology control of various aromatic polyimides representative as poly(4,4'-oxydiphenylene pyromelliteimide) was examined by using the phase separation during solution polymerization. Polymerizations of aromatic dianhydrides and aromatic diamines to the polyimides were carried out in poor solvents at 240-330 degrees C for 6 h with no stirring. Polymerization concentrations were from 0.25% to 3.0%. The polyimides were obtained as yellow precipitates. Two categorized morphologies were created, which were particles and crystals exhibiting lath-like and plate-like habits. These morphologies of polyimides could be selectively controlled by the polymerization conditions. The higher concentrations, less miscible solvents and lower temperatures were preferable to yield the particles via liquid-liquid phase separation. On the contrary, the lower concentration, miscible solvents and higher temperature were desirable to yield the crystals. The polyimide precipitates showed high crystallinity and possessed excellent thermal stability at which the 10 wt% loss temperatures in N-2 were in the range of 590-694 degrees C. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2006.11.061

リサイクル性に優れたセルフコンポジット型高強度・高耐熱性プラスチック材料の開発招待

山崎慎一

ポリファイル 44 ( 518 ) 30 - 34 2007年

Two-step formation of entanglement from disentangled polymer melt detected by using nucleation rate 査読

Shinichi Yamazaki, Fangming Gu, Kaori Watanabe, Kiyoka Okada, Akihiko Toda, Masamichi Hikosaka

POLYMER 47 ( 18 ) 6422 - 6428 2006年8月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

"How do chain molecules spontaneously entangle from completely disentangled polymer melt?" remains the most interesting unsolved problem. In order to solve this problem, we used the concept that the melt of "nascent" polymer crystallized during polymerization just after melting does not include any entanglements. We succeeded in detecting the increase of entanglement density v(e) with the increase of annealing time At above the equilibrium melting temperature before isothermal crystallization. The increase of v(e) was detected by observing the decrease of nucleation rate I from the melt of nascent polymer with different Delta ts. I is a very sensitive detector of entanglements because the nucleation is a rearrangement process of chains to the crystalline lattice through the disentanglement. Therefore, I is significantly suppressed with the increase of v(e). We found a two-step decrease of I with an increase of Delta t for the first time. This should correspond to a two-step increase of v(e) with an increase of Delta t. This indicates that simple entanglements such as twist or knot with lower order (one time knot) were formed within short time and then the complicated ones such as knot with higher order (two or three times knots) or loops (entanglements by loop conformation) were formed. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2006.07.010

Novel fluorine-containing poly(aryl ether amide)s derived from 2,3,4,5,6-pentafluorobenzoic acid 査読

Ken Tanaka, Natsuko Sato, Shinichi Yamazaki, Kunio Kimura, Yuhiko Yamashita

SEN-I GAKKAISHI 62 ( 7 ) 155 - 161 2006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：SOC FIBER SCIENCE TECHNOLOGY

Various amide-containing aryl fluorides were synthesized from 2,3,4,5,6-pentafluorobenzoic acid, and novel fifteen AA-BB type and three AB type fluorine-containing poly(aryl ether amide)s (F-PEA) were obtained by nucleophilic aromatic substitution reaction. The synthesized aryl fluorides possessed several reactive carbons for the nucleophilic attack and cross-linking reaction occurred at 100 degrees C. Polymerizations were carried out at 80 degrees C to avoid cross-linking and stopped just before gelation occurred. They had all para connected linear structures. The obtained F-PEAs showed excellent solubility and afforded tough transparent films by casting method. They also exhibited high Tg in the range of 179-273 degrees C depending on the molecular structure. They showed good thermal stability, and even though F-PEAs contained amide linkage into the repeating unit of polymer molecule, they exhibited excellent hydrophobicity due to the incorporation of 2,3,5,6-tetrafluoro-1,4-phenylene moiety.

DOI： 10.2115/fiber.62.155

Fabrication of poly(p-oxycinnamoyl) nano-scale particles 査読

Yoshito Hirai, Shin-ichiro Kohama, Shinichi Yamazaki, Kunio Kimura

SEN-I GAKKAISHI 62 ( 7 ) 167 - 174 2006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：SOC FIBER SCIENCE TECHNOLOGY

Fabrication of poly(p-oxycinnamoyl) (POC) nano-scale particles was examined by using self-seeding polymerization of (E)-4-acetoxycinnamic acid in liquid paraffin. The diameter of the POC spheres was very susceptible to the polymerization temperature and the temperature drop was very efficient to control the nucleation process by the adjustment of the degree of super saturation leading to the decrease in the diameter. The average diameter of the spheres prepared at 320 degrees C was 3.6 mu m, whereas, the temperature drop from 320 degrees C to 250 degrees C just before the nucleation afforded the POC microspheres having average diameter of 2.2 mu m. In order to prepare the nano-scale particles, only the self-seeding polymerization was not sufficient and the control of the growth process was additionally required. The POC particles having 600 nm of the average diameter were obtained by not only the temperature change from 320 degrees C to 250 degrees C and then 320 degrees C but also the addition of 4-octadecyloxybiphenyl as a coalescence inhibitor. The average diameter was in nano-scale, but the diameter distribution became broader with bimodality.

DOI： 10.2115/fiber.62.167

New attempt at preparation of fluorine-containing poly(ether ketone)s in supercritical carbon dioxide

Kunio Kimura, Shinichi Yamazaki, Patrick E. Cassidy, John W. Fitch, Sreenu R. Venumkbaka

岡山大学環境理工学部研究報告 11 ( 1 ) 93 - 97 2006年3月

Acceleration mechanism of growth rates under shear flow due to the oriented melt - The novel morphology of spiral crystal (spiralite) 査読

K Watanabe, K Okada, A Toda, S Yamazaki, T Taniguchi, K Koyama, K Yamada, M Hikosaka

MACROMOLECULES 39 ( 4 ) 1515 - 1524 2006年2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

Isothermal crystallization of three-dimensional (3D) spherulites from the bulky melt under low shear rate flow was Studied based on new in situ observation along a direction perpendicular to the flow velocity a adient plane (XZ plane) by means Of optical microscope, where X- and Z-axes are perpendicular and parallel to the flow direction, respectively. Spherulites are rotating. A novel "spiral pattern" was found oil the surface of the rotating "half-spherulite" near the surface of the melt for the first time. The half-spherulite is named "spiralite" which enabled us to have a visible image of the rotation of Spherulite. Hence, we could detect the growth rate around the Z-axis V(Z) and that around the X-axis V(X) by using the spiral pattern. We could experimentally obtain V(Z) > V(X) in this study. From kinetic viewpoint. this fact indicates that free energy for formation of a critical nucleus around file Z-axis is smaller than that around the X-axis. From this, it is concluded that the 1 oriented melt" is formed around the 7 axis. We proved it theoretically by showing that micro shear rate (Z) on the interface around the Z-axis significantly increases and chains will be elongated even when macro is low (y < 10 s(-1)). With increase of y(Z), the chain elongation will overcome the entropic relaxation, that results in formation of the "oriented melt". Crystallization mechanism under low shear flow is proposed that file growth rate of spherulite or shish is accelerated around interface, due to formation of the "oriented melt". Finally, we proposed a possible relationship between Inch Structure and crystallization under anisotropic and isotropic external fields.

DOI： 10.1021/ma050825z

Morphology control of aromatic polymers in concert with polymerization 査読

Kunio Kimura, Shin-ichiro Kohama, Shinichi Yamazaki

POLYMER JOURNAL 38 ( 10 ) 1005 - 1022 2006年

記述言語：英語出版者・発行元：NATURE PUBLISHING GROUP

Morphology control methods of aromatic polymers in concert with polymerization reaction are described in this review. Many attractive methods have been developed including reaction-induced phase separation of oligomers, epitaxial polymerization, shear-induced chain orientation during gelation, template-based polymerization, suspension polycondensation, solid-state polycondensation and liquid-liquid interfacial precipitation and so on. Among them, the reaction-induced phase separation of oligomers, in which there are two modes of crystallization and liquid-liquid phase separation, possess practically high potentiality to create novel polymer materials since it can control not only the morphology but also the molecular chain orientation. Ultimate goal is the embodiment of the nature system in a flask, that is, the control of the materials from primary structures to super structures. The morphology control methods by using polymerization reaction afford the valuable methodology for the three-dimensional structure architecture.

DOI： 10.1295/polymj.PJ2006083

Morphology control of polybenzimidazole by using reaction-induced phase separation of oligomers during solution polymerization

Shin-Ichiro Kohama, Shinichi Yamazaki, Kunio Kimura, Jin Gong, Kaoru Shimamura

Polymer Preprints, Japan 55 ( 2 ) 2852 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

This paper deals with a new finding on the morphology control of poly[2,2′-(p-phenylene)-5,5′-bibenzimidazole] (PBI) by using the reaction-induced crystallization of oligomers during solution polymerization. Polymerizations of 3,3′-diaminobenzidine and diphenyl terephthalate or terephthalic acid were carried out at 350°C for 6 hours in poor solvent such as dibenzyl toluene mixture to induce the crystallization of oligomers. Bundle-like aggregates of PBI nanofibers and plate-like PBI crystals were prepared with high yields. The values of inherent viscosity of FBI were 0.49 - 0.58 dL/g. Obtained crystals possessed high crystallinity measured on WAXS and good thermal stability. The morphology of the products was drastically influenced by the end-group structure of phase separated oligomers.

Nucleation and entanglement of cyclic polyethylene

Shouichi Ida, Shinichi Yamazaki, Kunio Kimura

Polymer Preprints, Japan 55 ( 2 ) 3125 - 3126 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

Previously, we have shown the hierarchised model of entanglements of polymer chains based on melt annealing time Δt dependence of nucleation rate I of "nascent" linear polyethylene (nascent L-PE). This work showed the validity of above model and role of "knot" entanglement in the nucleation of polymers using cyclic polyethylene (C-PE) which can not form the knot entanglement. We found that I of C-PE was remarkably larger than that of L-PE. Moreover, we found that I of C-PE monotonically decreased with increasing Δt. These imply that the knot entanglement plays an important role in the nucleation.

Synthesis of novel fluorine-containing poly(ether sulfone)s by using chemical modification reaction

Shunsuke Masaki, Ai Nishichi, Shinichi Yamazaki, Kunio Kimura

Polymer Preprints, Japan 55 ( 1 ) 189 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

This paper described the synthesis of novel fluorine-containing aromatic poly(ether sulfone)s (F-PES) by the oxidation of the corresponding fluorine-containing polythioethers (F-PTEs) derived from 2,3,4,5,6- pentafluorobenzoic acid. F-PTEs were synthesized by nucleophilic aromatic substitution reaction at relative low temperature in DMF. F-PTEs obtained by stopping just before the gelation were all para connected linear structures. The obtained F-PESs showed higher Tg than that of F-PTEs due to the introduction of sulfone units. They also exhibited excellent solubility and good hydrophobicity due to the incorporation of 2,3,5,6-tetrafluoro-1,4-phenylene moiety.

Nonstoichiomeric polymerization of polyimide by using reaction-induced crystallization of oligomers

Kanji Wakabayashi, Takuya Ito, Shinichi Yamazaki, Kunio Kimura

Polymer Preprints, Japan 55 ( 1 ) 281 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

Nonstoichiometric preparation of poly(4,4'-oxydiphenylene pyromelliteimide)(Kapton) from pyromellitic dianhydride (PMDA) and 4,4'-oxydianiline (ODA) was examined by using reaction-induced crystallization of oligomers. When the polymerization was carried out under stoichiometric condition, the crystals having ηinh of 1.58 dL/g were obtained. Under the excess ODA, ηinh was insensitive toward the imbalance of stoichiometry, and suprisingly, ηinh became 1.63 dL/g even under 50 mol% excess. In the polymerization under nontoichiometric condition, the terminated oligomers precipitated to form the crystals and the solid-state polymerization proceeded with the elimination of terminated oligomer unit in oligomer crystals resulting in high molecular weight.

Improvement of adhesion between liquid crystalline polymer film and epoxy by cold plasma treatment

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

Polymer Preprints, Japan 55 ( 1 ) 2349 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

We investigated the surface modification of thermotropic liquid-crystalline polymer (LCP) film made of wholly aromatic copolyester by O2 reactive-ion-etching (RIE) and O2, N2, N 2/H2(7/3) direct-plasma (DP) to improve the adhesion and the long-term reliability of the adhesion between the LCP film and epoxy, which is typically used as bonding sheet for printed circuit boards. About the peel strength before and after Pressure Cooker Test (PCT), which was conducted to determine the long-term reliability, the peel strength before PCT was increased with decreasing pressure in O2, N2 DP, whereas the peel strength after PCT was decreased with decreasing pressure in O2 RIE and O2, N2 DP . The XPS analysis conducted on the LCP film surface treated with O2 RIE and O2 DP implied that a higher number of phenol hydroxyl groups were generated at low-pressure and the peel strength before and after PCT was affected. Moreover, it is speculated that if N functional groups are introduced by the plasma treatment of the gas containing N2, the decrease of the peel strength after PCT will become significant. The surface roughness of the film was increased with increasing pressure in O2 RIE, and it was assumed that the peel strength before and after PCT was based on the synergistic effect of functional groups and the surface roughness.

Preparation of polybenzimidazole nanofibers by using reaction-induced crystallization of oligomers during solution polymerization

Shin-Ichiro Kohama, Jin Gong, Shinichi Yamazaki, Kunio Kimura, Kaoru Shimamura

Polymer Preprints, Japan 55 ( 1 ) 546 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

This paper deals with our new finding on the fabrication of poly[2,2'-(p-phenylene)-5,5'-bibenzimidazole] (PBI) nanofibers by using the crystallization of oligomers during solution polymerization. Polymerizations of 3,3'-diaminobenzidine and diphenyl terephthalate were carried out at 320 and 350°C for 6 hours in poor solvents to induce the crystallization of oligomers. The solvents used in this study were liquid paraffin (LPF) and Barrel Therm 400 (BT4, Matsumura Oil Co., Ltd.), which is the mixture of dibenzyl toluene. In the polymerizations in LPF, plate-like crystals of PBI were obtained and their inherent viscosities (ηinh) were 0.21 - 0.27 dL/g. On the other hand, in the polymerization in BT4, the bundle-like aggregates of PBI nanofibers were prepared with quantitative yields. The diameter of each nanofibers was 20 - 100 nm. The values of ηrinh of PBI nanofibers were 0.35 - 0.58 dL/g and they were higher than those in LPF. These nanofibers possessed extremely high crystallinity measured on WAXS and good thermal stability. The morphology was drastically influenced by the solvent, and the control of miscibility is of great importance for the fabrication of PBI nanofibers.

Possibility of disentanglement process of condensation polymer by transesterification proof by growth rate of spherulite

Takuya Oka, Shinichi Yamazaki, Kunio Kimura

Polymer Preprints, Japan 55 ( 1 ) 818 2006年

記述言語：日本語掲載種別：研究論文（国際会議プロシーディングス）

In order to proof of the possibility of disentanglement process of condensation polymers via transesterificartion, we measured the growth rate of spherulite (G) of PLLA as a function of melt annealing time (Δt) before isothermal crystallization. We prepared three PLLA samples by means of reaction induced crystallization of oligomers during polymerization. For the sample with unclear crystal habit, we found that G was almost constant at Δt&lt
30 min, and then monotonially decreased with increasing Δt. From GPC measurements, we confirmed that molecular weight did not change and molecular weight distribution became broad. This implies that condensation polymers within the melt disentangle via transesterification.

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