国内精品国产三级国产在线专_欧美日韩在线播放一区二区_成人xxxx视频_欧美激情视频一区_色女人综合av_久久久亚洲影院_久久久久久九九_成人免费网站在线_日韩美女毛茸茸_狠狠干一区二区

Links
Contact Info.
  • Address:天津市西青區(qū)賓水西道399號
  • Zip:300387
  • Tel:010-64437861
  • Fax:
  • Email:[email protected]
Current Location :> Home > Publications > Text
1. Phase Transition and Transition Kinetics of a Thermotropic Poly(amide-imide) Derived from 70% Pyromellitic Dianhydride, 30% Terephthaloyl Chloride, and 1,3-Bis[4-(4’-aminophenoxy)cumyl]benzene
writer:S. Liu, T. Chung,* J. X. Geng, E. Zhou, S. Tamai
keywords:Phase Transition and Transition Kinetics
source:期刊
specific source:Macromolecules 2001, 34, 8710-8719
Issue time:2001年

The phase transition and transition kinetics of a liquid crystalline copoly(amide-imide) (PAI37), which was synthesized from 70 mol % pyromellitic dianhydride, 30 mol % terephthaloyl chloride, and 1,3-bis[4-(4¢-aminophenoxy)cumyl]benzene, was characterized by differential scanning calorimetry, polarized light microscopy, X-ray diffraction, and rheology. PAI37 exhibits a glass transition temperature at 182 °C followed by multiple phase transitions. The crystalline phase starts to melt at 220 °C and forms smectic C (SC) phase. The SC phase transforms into smectic A (SA) phase when the temperature is above 237 °C. The SC to SA transition spans a broad temperature range in which the SA phase vanishes and forms isotropic melt. The WAXD fiber pattern of PAI37 pulled from the anisotropic melt revealed an anomalous chain orientation, which was characterized by its layer normal perpendicular to the fiber direction. The transition kinetics for the mesophase and crystalline phase formation was also studied.