聚碳酸亚丙亚乙酯的合成和生物降解

Synthesis and Biodegradation of Polypropylene ethylene carbonate

由ＣＯ２和环氧丙烷的催化共聚制备了聚碳酸亚雨酯（ＰＰＣ），向ＰＰＣ引入环氧乙烷结构单元得到聚碳酸亚西亚乙酯（ＰＰＥＣ），用１ＨＮＭＲ等进行了结构表征，并用土埋法进行了生物降解性能的测定，结果表明ＰＰＣ仅在分子量很低时才具备显著的生物降解性能；而ＰＰＥＣ的生物降解速度高于分子量相近的ＰＰＣ．此外，土埋三月后共聚物的组成和分子量都保持基本不变，表明实验条件下生物降解主要在聚合物的表面进行．

Copolymerization of CO2,ethylene oxide, and propylene oxide led to form aterpolymer poly (propylene ethylene carbonate) (PPEC) o Under soil burial condition, the terpolyme.r showed biodegradability higher than poly (propylene carbonate)(PPC), which was formed by the copolymerhation without ethylene oxide andshowed obvious biodegradability only when its molecular weight was as low as 6×103. In addition, it was found that the biodegradability of PPEC was enhanced withincreasing the ethylene oxide molar fraction in the polymer chain and decreasing itsmolecular weight. During biodegradation, the bulk chain structure and molecularweight of the polymer were found to keep unchanged, indicating that biodegradationoccurs mainly on the polymer surface.