中文摘要：

采用溶剂涂膜法制备了共聚组成不同的（3-羟基丁酸酯）-（4-羟基丁酸酯）共聚物[poly（3HB-co-4HB）]生物可降解膜。通过土壤和猪胰脂肪酶降解实验,考察了降解过程中样品质量、分子量及表面形态的变化。结果表明,土壤降解和酶降解都经过表面腐蚀过程,无定形态首先降解,样品质量逐渐损失,分子量逐渐减少;结晶度对膜的腐蚀形貌有很大的影响,降解速率都随4HB含量的增加而增加;脂肪酶降解速率比土壤降解速率快,但分子量减少的程度不及土壤降解,并且在降解过程中出现了小分子量的低聚物。

英文摘要：

Biodegradable films of poly（3-hydroxybutyrate-co-4-hydroxybutyrate） copolymers with different compositions were prepared by a solvent evaporation technique. The weight losses and changes in molecular weight and surface morphology were investigated after degradation in soil and in an aqueous of porcine pancreas lipase for different times. It was found that degradation in soil and by porcine pancreas lipase both resulted in surface erosion with loss of weight and decrease in molecular weight and that the rate of degradation increased as the proportion of 4-hydroxybutyrate in the copolymer increased. Surface erosion began in an amorphous phase and the degree of crystallinity had a significant influence on corrosion morphology. The rate of degradation by porcine pancreas lipase was faster than that in soil, but the decrease in molecular weight was less than that in soil. Moreover, oligomers appeared during the lipase degradation process.