Abstract: In this paper，the in virto degradation behavior of PHB/PLLA[poly (?-hydroxybutyrate)/ poly (L-lactide)] blends and PHB/PLLA/PEO [poly (?-hydroxybutyrate)/poly (L-lactide)/poly (ethylene oxide)] blends was studied by changing weight retention，thermal properties，the morphology of PHB/PLLA and PHB/PLLA/PEO patch in phosphate buffered saline (PBS)/ lysozme at 37 ℃. It was founded that the degradation rates of PHB was not affected by PLLA，whereas PEO adding to PHB/PLLA blends led to the acceleration of PHB and PLLA degradability，so the degradation rate of PHB/PLLA was accelerated.

Key words: poly(b-hydroxybutyrate), poly (L-lactide), poly (ethylene oxide), degradation

摘要： 对聚β-羟基丁酸酯/聚乳酸（PHB/PLLA）及聚β-羟基丁酸酯/聚乳酸/聚氧乙烯（PHB/PLLA/PEO）膜状样品在37 ℃磷酸缓冲溶液（PBS）/溶菌酶中的降解行为进行了研究，通过定期观察质量损失、降解过程中的热力学性质及样品表面形态变化，发现PHB/PLLA共混未能提高PHB的降解速度，而PEO加入到PHB/PLLA体系中显著提高了PHB、PLLA的降解速度，进而提高了PHB/PLLA共混体系的降解速度。

关键词: 聚&beta, -羟基丁酸酯, 聚乳酸, 聚氧乙烯, 降解