聚(天冬氨酸-co-乳酸)的合成及结构与性能

由聚(琥珀酰亚胺-乳酸)的碱溶液水解反应制备了含有亲水性羧基的聚(天冬氨酸-co-乳酸)(PAL)。用IR、NMR、DSC、元素分析等方法表征了PAL的组成和结构。结果表明,PAL中的聚乳酸链段为间同立构或无规立构,由此推断丙交酯在开环聚合反应时发生了酯交换或链转移反应,导致聚乳酸链段产生消旋现象;聚合反应机理是羟基引发的聚合,获得了无定型态聚合物PAL。由于共聚反应中丙交酯熔体的蒸发损耗,合成的PAL中聚天冬氨酸的含量高于理论值。

Preparation and Structural Analysis of Poly(Aspartic Acid-co-Lactic Acid)

poly(aspartic acid-co-lactic acid)(PAL) with hydrophilic reactive amido and carboxyl was prepared by alkali hydrolysis of poly(succinimide-lactic acid).The composing and structure of PAL were characterized by IR,NMR,DSC and elemental analysis.The results of characterization show that PAL is amorphous and poly(lactic acid) units in it is not stereospecific.Therefore,it can be concluded that the recemization occurs in the ring-opening of L-lactide by the transesterifications and chain transfer,and the reactiv...