Author Kimura, Kunio|
Published Date 2001-08
Publication Title 環境制御
Volume volume23
Content Type Others
JaLCDOI 10.18926/fest/11649
Title Alternative Morphology Control of Aromatic Polymers during Polymerization
FullText URL 001_221_227.pdf
Author Yamashita, Yuhiko| Kimura, Kunio| Tsugita, Hiroshi| Yokoyama, Fumiyoshi|
Abstract Morphology and formation mechanism of poly (4'-oxy-4-biphenylcarbonyl) (POBP) crystals obtained by solution polymerization were firstly treated. It was concluded that the formation mechanism of the bundlelike aggregates of fibrillar crystals in POBP was fundamentally simillar to that in POB whiskers. Secondly the copolymerization effects of m-acetoxybenzoic acid and 4-(4-acetoxyphenyl) benzoic acid on the morphology of POB whiskers were studied. The experimental results strongly supported our proposal for the formation mechanism of whiskers which was consisted of crystallization of oligomers with a critical length as lamellae from solution and solid state polymerizationof oligomers between lamellae. Finally, the formation mechanism of poly (p-oxycinnamoyl) spherical products during solution polymerization was treated. The formation of these spherical products could be understood by overlapped phase diagram of melting depression curve and consolute curve of oligomers-solvent system.
Keywords morphology control aromatic polymers phase separation polymer whisker polymer beads rigid rod polymers
Publication Title 岡山大学環境理工学部研究報告
Published Date 1996-03
Volume volume1
Issue issue1
Start Page 221
End Page 227
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313893
JaLCDOI 10.18926/fest/11482
FullText URL 011_093_097.pdf
Author Kimura, Kunio| Yamazaki, Shinichi| Cassidy Patrick E.| Fitch John W| Venumbaka Sreenu R.|
Abstract Fluorine-containing poly(ether ketone)s was synthesized by the nucleophilic aromatic substitution reaction of 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane and 4,4'-bis(2,3,4,5,6-pentafluorobenzoyl) diphenyl ether in super-critical CO(2). Polymerizations were carried out at 80℃ for 6 hours under 5000 psi of CO(2) pressure, which was super-critical phase. Polymerization concentration was 0.5 g of polymer in 10 - 12 mL of CO(2). The polymer was not obtained in CO(2) due to the insolubility of both the potassium bisphenoxide and the polymer into CO(2). However, the polymer was formed by an addition of DMAc and NMP in CO(2), even though molecular weight was not so high. Very small amount of co-solvents which were immiscible with CO(2) was effective, and it was 1/20 - 1/25 amount of the solvent used in the conventional poly(ether ketone) synthesis. The polymerization mechanism was also discussed.
Keywords super-critical carbon dioxide plastics high performance environmentally benign
Publication Title 岡山大学環境理工学部研究報告
Published Date 2006-03-15
Volume volume11
Issue issue1
Start Page 93
End Page 97
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313564
JaLCDOI 10.18926/fest/11477
Title Alternative Efficient Chain Extension Reaction of Poly (butylene terephthalate) by using Crystallization
FullText URL 012_167_171.pdf
Author Ihara, Seiji| Shiroma, Hisashi| Yamazaki, Shinichi| Kimura, Kunio|
Abstract 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.
Keywords Polyester material recycle crystallization chain extension reaction
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 167
End Page 171
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002314029
JaLCDOI 10.18926/fest/11473
Title Alternative Acceleration of Formation of Shish under Flow by Addition of Irregular Shaped Particles
FullText URL 012_157_160.pdf
Author Yamazaki, Shinichi| Wakabayashi, Kanji| Mizuma, Kenta| Kimura, Kunio|
Abstract 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.
Keywords shish crystallization polypropylene shear flow elongation injection molding
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 157
End Page 160
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313610