| Summary: | 碩士 === 中原大學 === 化學工程研究所 === 86 === In this study, two series of poly(ester-imide)s were synthesizedby using direct polycondensation. In the first part, a seriesof novel diimide-diacid monomers were synthesized by trimelliticanhydride (TMA) with various diamines, respectively. The fullyaromatic heat-resistant poly(ester-imide)s were prepared by thedirect polycondensation from the imide-diacids with variousaromatic diols in the presence of DPCP, LiCl, and pyridine. In the second part, another series of novel semi-aromaticthermotropic liquid crystalline poly(imide-ester)s were alsoprepared with the similar method. The effects of the amount ofLiCl, kinds of solvent, and the reaction time, the structure ofbenzidine moiety on the thermal properties and molecular weightof the synthesized poly(imide-ester)s, were investigated. Thethermal properties of the synthesized polymers were examined byDSC, polarized microscope with a heating stage, and TGA. In the first part, the PI2On series exhibited a higher thermalstability than the other series. The PI2On and PI4On seriesexhibited good solubilities in NMP, DMAC, DMF and DMSO. In thesecond part, it was found that semi-aromatic poly(imide-ester)swith methylene spacer, n = 6, 10, exhibits LC phase. Both Tm and Ti decreased with the increase of the length of spacer.
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