Studies on the Synthesis and Properties of Semi-Aromatic Thermotropic Liquid Crystalline Poly(amide-ester) and Polyester Elastomers

• Main Authors: Chung Li-Ling, 鍾麗玲
• Other Authors: Chang Teh-Chou
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/55487298959277022208

碩士 === 中原大學 === 化學工程研究所 === 86 === A series of semi-aromatic thermotropic liquid crystalline poly(amide-ester) and polyester elastomers were prepared by direct polycondensation from various aromatic diacid (e.g. TPA, DBAC or PEG4) with various aromatic diamine (e.g. ODA, BDAM or NDAM), various diols (e.g. PhHQ, BPO, MHQ, BP, PEG-200, PEG-600, PEG-1000 or isosorbide), respectively, in the presence of diphenyl chlorophosphate(DPCP), LiCl and pyridine. In order to investigate the relationship between the structures and the LC properties of the synthesized poly(amide-ester) and polyester elastomers, all of the synthesized polymers were examined by DSC, polarized microscope with a heating stage, WAXD, TGA and DMA. For preparing LC poly(amide-ester)s and polyester elastomers with long soft segments, it was found that aspect ratio of the hard segments should be extented. However, on the other hand, the transition temperatures of the hard segment were suppose to be reduced to show LC properties, because the thermostabilities of the soft segments were relatively poor. Synthesizing alternating LC elastomers could lower the transation temperation temperature effectively. In this study, we also attempted to prepare novel cholesteric LC elastomers by introducing the amount of isosorbide, as a chiral diol monomer, which is lower than 25 mole ﹪. In addition, the synthesized poly(amide-ester) and polyester elastomers possessed excellent thermostabilties (the 5 wt ﹪ loss temperature is higher than 400 ℃).