目的 研究P(3HB-co-4HB)/PBS共混材料在脂肪酶溶液中的生物降解性能。方法 将P(3HB- co-4HB)/PBS共混材料置于脂肪酶溶液中进行酶解实验，利用质量损失率、扫描电镜(SEM)、X射线衍射(X-RD)和偏光显微镜(POM)等测试手段或指标，对材料的生物降解性能进行分析。结果 质量损失率与SEM结果表明，实验用脂肪酶对P(3HB-co-4HB)的降解效果不明显，而对PBS有着较为显著的降解效果。X-RD分析表明，P(3HB-co-4HB)/PBS共混材料在19.9°和22.7°处的结晶衍射峰强度随酶解时间不断下降，表明主要是PBS组分发生了降解。POM结果表明，P(3HB-co-4HB)酶解前后球晶的形态基本不变。结论 实验用脂肪酶对PBS酯键的水解相对容易，而对P(3HB-co- 4HB)酯键的水解难度较大，P(3HB-co-4HB)/PBS共混材料在酶解时，存在PBS优先降解的情况。脂肪酶酶解对材料的晶区与非晶区并没有选择性。

The work aims to research the biodegradability of P(3HB-co-4HB)/PBS blends in the lipase solution. P(3HB-co-4HB)/PBS blends were placed in the lipase solution for experiments on enzymolysis. Biodegradability of the blends was analyzed by means of weight loss rate, scanning electron microscopy (SEM), X-ray diffraction (X-RD) and polarizing microscope (POM). The weight loss rate and SEM analysis showed that the lipase degradation effect on P(3HB-co-4HB) was not obvious, while such effect on PBS was more significant. XRD analysis showed that the intensity of the blends’ crystal diffraction peak at 19.9° and 22.7° decreased with the enzymolysis time, which indicated that the main degraded component was PBS. The POM results showed that the spherulite morphology of P(3HB-co-4HB) before and after enzymolysis was basically unchanged. The enzymic hydrolysis of PBS ester bond is relatively easy, while the hydrolysis of P(3HB-co-4HB) ester bond is difficult. PBS is preferentially degraded in the P(3HB-co-4HB)/PBS blends in the lipase solution. Moreover, there is no selectivity on the crystal area and amorphous area of materials during enzymatic degradation of lipase.