胆固醇-聚(D,L-乳酸)的直接熔融聚合法制备与表征  

Direct synthesis of poly(D,L-lactide-cholesterol) via melt copolycondensation and its characterization

作　　者：赵海军[1] 汪朝阳[1] 侯晓娜[1] 李雄武[1] 

机构地区：[1]华南师范大学化学与环境学院化学系,广东广州510006

出　　处：《化学试剂》2007年第1期39-42,共4页Chemical Reagents

基　　金：广东省自然科学基金博士科研启动基金资助项目(5300082);华南师范大学博士启动基金资助项目(670093)

摘　　要：取代传统的丙交酯开环共聚法,直接以外消旋乳酸(D,L-LA)为原料,以廉价的氯化亚锡为催化剂,采用熔融聚合法合成胆固醇-聚(D,L-乳酸)共聚物。分别考察不同投料比、预聚时间和熔融共聚时间的影响,并用FT-IR1、HNMR、GPC、DSC等进行了系统表征。当投料比n(胆固醇)∶n(乳酸)=1∶66、预聚4 h、熔融共聚10 h、催化剂用量0.3%时,以85%的产率生成了重均相对分子质量(Mw)达3 600(分散度Mw/Mn=1.24)的共聚物。新方法步骤少、路线简捷,相对分子质量可以达到丙交酯开环共聚法的水平,且成本更加低廉。Using D, L-lactic acid （ D, L-LA） as the starting material and cheap SnCl2 as the catalyst, poly（ D, L-lactide-cholesterol） was directly synthesized via melt copolycondensation in place of the traditional ring-opening polymerization of lactide. The copolymer was systematically characterized by FT-IR, ^1HNMR, DSC and GPC. The optimal synthetic conditions, including the feed molar ratio, the prepolymerization time and polymerization time, were discussed. When being catalyzed by 0.3 % SnCl2 at a feed molar ratio of cholesterol to lactic acid equating to 1 ： 66 and a reaction temperature of 140 ℃, the reaction mixture after prepolymerization for 4 h followed by polymerization for 10 h gave the target product with a yield of 85%. The weight-average molecular weight （Mw） of the copolymer was 3 600, which was higher compared to that achieved by the ring-opening polymerization of lactide. At the same time, the novel direct copolycondensation method was cheaper and more practicable than the traditional method of ring-opening polymerization of lactide.

关 键 词：外消旋乳酸(D L-LA) 胆固醇-聚(D L-乳酸) 熔融聚合 直接合成 表征 

分 类 号：O633[理学—高分子化学]