Citation:
WANG Pingping, ZHANG Hongzhi. PREPARATION OF LIQUID CRYSTALLINE COPOLYESTERS WITH SPACERS BASED ON BISPHENOL-A, BISPHENOL-S OR POLYSULFONE BY DIRECT POLYCONDENSATION[J]. Chinese Journal of Polymer Science,
1989, 7(1): 9-15.
PREPARATION OF LIQUID CRYSTALLINE COPOLYESTERS WITH SPACERS BASED ON BISPHENOL-A, BISPHENOL-S OR POLYSULFONE BY DIRECT POLYCONDENSATION
摘要:
Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild conditions. The electron-rich hydroxyl groups of bisphenols favoured the polycondensation reaction and the order of relative reactivities of bisphenols is as follow: bisphenoI-A> hydroquinone ～ bisphenol-S> chlorohydroquinone. The mesomorphic properties of copolyesters were examined by birefringence under polarzing microscope,melt transparency,DSC and X-ray diffraction.The minimum molar fraction of mesogenic units needed for the appearance of liquid crystallinity is not higher than0.1 despite of the different varieties and lengths of the spacers studied.
English
PREPARATION OF LIQUID CRYSTALLINE COPOLYESTERS WITH SPACERS BASED ON BISPHENOL-A, BISPHENOL-S OR POLYSULFONE BY DIRECT POLYCONDENSATION
Abstract:
Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild conditions. The electron-rich hydroxyl groups of bisphenols favoured the polycondensation reaction and the order of relative reactivities of bisphenols is as follow: bisphenoI-A> hydroquinone ～ bisphenol-S> chlorohydroquinone. The mesomorphic properties of copolyesters were examined by birefringence under polarzing microscope,melt transparency,DSC and X-ray diffraction.The minimum molar fraction of mesogenic units needed for the appearance of liquid crystallinity is not higher than0.1 despite of the different varieties and lengths of the spacers studied.
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