標題: Miscibility and transesterification in blends of liquid crystalline copolyesters and polyarylate
作者: Tyan, HL
Wei, KH
材料科學與工程學系
Department of Materials Science and Engineering
關鍵字: miscibility;transesterification;kinetics;polyarylate;liquid crystalline copolyesters
公開日期: 1-八月-1998
摘要: Blends of poly(oxybenzoate-p-ethylene terephthalate) (POB-PET) and polyarylate were confirmed to be a partially miscible system by differential scanning calorimetry. When 60/40 POB-PET/PAr blend was annealed at high temperature (above 270 degrees C) for several minutes, the ester-ester interchange( transesterification)in the blend took place immediately, as evidenced by Fourier Transformed infrared analyses. The analysis of the blend annealed at 290 degrees C by H-1-C-13 nuclear magnetic resonance disclosed that there were four new diads appearing in 15 min and an additional one produced in 60 min during the heat treatment. The miscibility between POB-PET and polyarylate increased with the mol concentration of these new diads judging from differential scanning calorimetry. The evolution of the concentration of the diad ethylene glycol-isophthalate during the annealing can be described by a second-order reaction. The activation energy of forming the diad ethylene glycol-isophthalate was 26.5 kcal/mol, and the preexponential factor for the transesterification reaction is 3.7 x 10(8) min(-1). (C) 1998 John Wiley & Sons, Inc.
URI: http://hdl.handle.net/11536/32472
ISSN: 0887-6266
期刊: JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
Volume: 36
Issue: 11
起始頁: 1959
結束頁: 1969
顯示於類別:期刊論文


文件中的檔案:

  1. 000074604600017.pdf