| Summary: | 碩士 === 南台科技大學 === 化學工程與材枓工程系 === 100 === A series of biodegradable homopolyesters were synthesized from polyoxalate and different diols (1,4-CHDM, 1,3-PDO and 1,4-BDO) catalyzed by transestrification polycondensation reaction in the bulk. In addition, the DSC of the resulting homopolyesters show higher degree of crystallinity , thus copolyesters added to MA (C=C) decreased crystallization and melting. biodegradable poly(oxalate ester urethanes) was synthesized by the polymerization of copolyesters (PCMA diols) and 4,4`-diphenylmethane diisocyanate (MDI) reacted with polyethylene glycol (PEG 2000) or castor oil (CO) as a long linear chain extender. The Tg influenced by the ratio of the soft-segment to the hard-segment. The PU properties were investigated using Fourier transform infrared (FTIR) spectroscopy, molecular weight, differential scanning calorimetry, mechanical analysis and thermogravimetry. The polyoxalate -based polyurethanes showed higher elongation at break, up to 2300%. The hydrolytic degradation of the polyesters and polyurethane ware determined by monitoring the normalized weight loss of polyester and polyurethane films with time in phosphate buffer pH 7.2 at 37℃. The rate of hydrolytic degradation follows the path ECPU＞PCMA＞CMPU＞CPCOU。
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