First,the polylactic acid-polyethylene glycol (PLA-PEG) copolymer was synthesized from lactic acid and polyethylene glycol by direct polycondensation.Then,4-(3-acryloxy-2-hydroxy) propyloxy-2-hydroxy- polylactic acid-polyethylene (AGE-PLA-PEG) was synthesized from 1-allyloxy-2,3-epoxy propane (also called allylglycidyl ether,AGE) and PLA-PEG catalyzed by Zn.Finally,in the presence of platinum compound as a catalyst,a polysiloxane with side chains of degradable PLA-PEG was synthesized by hydrosilylation of AGE-PLA-PEG with polyhydromethyl-siloxane (PHMS).The structures and properties of the products were determined.The results indicate that the molecular weight distribution of PDMS-g-PLA-PEG has broadened comparing with PHMS.Because of the degrade of PLA-PEG side-chains,the contact angle of the PDMS-g-PLA-PEG film with water increased with increasing times.%以乳酸和聚乙二醇为原料,直接缩聚法制备出聚乳酸-聚乙二醇可降解嵌段共聚物,再将烯丙基缩水甘油醚和所得的嵌段共聚物在锌粉的作用下得到带有α烯基反应性官能团的大分子单体,然后在铂催化剂的作用下,合成了一种带有可降解侧链的亲水性聚硅氧烷(PDMS-g-PLA-PEG).对产物的结构、相对分子质量及其分布、热性能及成膜的表面性能等进行了研究.结果表明,由于分子链中硅氢键分布的不均匀性和聚乳酸-聚乙二醇共聚物分子量分布的不均一性,产物的分子量分布相对较宽,达到了1.87.由于聚乳酸-聚乙二醇共聚物侧链逐渐降解,所以PDMS-g-PLA-PEG所成的膜与水的接触角将随着时间的延长而逐渐增大,30天后从42°增至92°.
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