【作者】 刘健；

【导师】 夏宇正；

【作者基本信息】 北京化工大学 ， 材料学， 2006， 硕士

【摘要】 聚乳酸(PLA)及共聚物是一类生物相容性和生物降解性均优的医用高分子材料，在药物释放和组织修复等方面具有广泛的应用前景，但因聚乳酸本身疏水性大致使其应用范围受到限制。本文以改善其亲水性为目的，通过ATRP法将水溶性的聚乙烯基吡咯烷酮(PVP)链段引入聚乳酸链段中，制得了PLA-b-PVP及PVP-b-PLA-b-PVP共聚物，对其进行了表征，并系统研究了各因素对共聚物结构及降解性能的影响规律，所得主要结果如下： (1)通过直接缩聚制得了聚乳酸和双端羟基聚乳酸(HO-PLA-OH)，并用~1H-NMR、IR、GPC对其进行了表征。得到了双端羟基聚乳酸(HO-PLA-OH)的最适工艺条件，所得HO-PLA-OH的数均分子量高达3700。 (2)通过PLA和HO-PLA-OH与2-溴代丙酰溴反应，制备了溴端基的聚乳酸(PLA-Br和Br-PLA-Br)，用~1H-NMR、IR对其进行了表征，并通过羟值法间接测得PLA-Br中溴含量为0.73mol Br／mol PLA-Br，Br-PLA-Br中的溴含量为1.91mol Br／mol Br-PLA-Br。 (3)以PLA-Br和Br-PLA-Br为大分子引发剂、CuBr／2，2’-Bpy为催化剂，实现了乙烯基吡咯烷酮的ATRP的聚合，~1H-NMR、IR分析更多还原

【Abstract】 Polylactide (PLA) and its copolymers are a kind of much better biocompatible and biodegradable polymers and are being increasingly used in medicine and organ fields. However, this kind of polymers is still limited in above applications due to its intrinsic hydrophobicity. In this paper, a novel amphiphilic block copolymers of poly-N-vinylpyrrolidone (PVP) and poly(D, L-lactide) were synthesized by atom transfer radical polymerization (ATRP). The degradated behaviours of copolymers were also studied in detail. The main conclusions can be drawn as follows:(l)Polylactide and hydroxyl-both terminated polylactide (HO-PLA-OH) were prepared by bulk melt polycondensation. The products were characterized by IR, ~1H-NMR and GPC. The results showed that the structure of two products was accord with designed structure. The molecular weight of HO-PLA-OH was high to 3700.(2)The functional macromolecular initiators (PLA-Br and Br-PLA-Br) were respectively prepared by reaction of polylactide or更多还原