中文摘要：

.采用己二醇对聚丁二酸丁二醇酯（PBS）改性,合成了不同比例、分子质量均在6×105左右的聚丁二酸丁二醇/己二醇酯（PBSH）,并以其为底物分别在2种不同的有机溶剂氯仿（CHCl3）和四氢呋喃（THF）中,研究了洋葱假单胞菌（PC）脂肪酶对其催化降解规律和溶剂效应.以GPC测试了共聚物降解前后的分子质量变化;以TG分析了酶降解共聚物前后热性能的变化;以MALDI-TOF-MS对降解产物进行了分析.研究结果表明：PBSH在2种溶剂中都能快速降解;降解60 h后2种共聚物的相对分子质量均减小,分子质量分布均变宽;但在氯仿中酶催化活性更高,PBSH降解速率更快;降解前后热失重5％时热分解温度均降低;MALDI-TOF-MS结果表明：在2种溶剂中降解产物中含SH（丁二酸己二醇酯）片段较多,且氯仿中降解产物种类更多,并易于成环.

英文摘要：

Aliphatic copolymers PBSH was synthesized by PBS modified with hexane,whose relative molecular weight was about 6 × 105. The enzymatic degradation and solvent effect of the copolymers with the PC lipase in chloroform and tetrahydrofuran was studied. The change of relative molecular weight and thermal stability were evaluated by GPC and TG. The degradation products were analyzed by mass spectrometry. The results showed that PBSH showed a fast degradation rate in both chloroform and tetrahydrofuran. But the lipase showed a higher activity and PBSH showed a faster degradation rate in chloroform than tetrahydrofuran. After degradation of 60h,relative molecular weight and the weight loss rate for 50 % of PBSH decreased while the molecular weight distribution broader. The analysis results of mass spectrometry showed that the degradation products in the two kinds organic solvents contained SH section, however the kind of degradation products from chloroform were more than THF,and easier to loop.