直接熔融聚合法合成聚(乳酸-缬氨酸)  

Synthesis of Poly(lactic acid-co-valine) via Direct Melt Copolycondensation

作　　者：侯晓娜[1] 汪朝阳[1] 罗玉芬[1] 叶瑞荣[1] 

机构地区：[1]华南师范大学化学与环境学院化学系,广州510006

出　　处：《应用化学》2009年第3期273-276,共4页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(20772035);广东省自然科学基金博士科研启动基金(5300082)资助项目

摘　　要：以廉价的外消旋乳酸(D,L-LA)和缬氨酸(Val)为原料,以氧化亚锡为催化剂,采用熔融聚合法合成了新型生物材料聚(乳酸-缬氨酸)共聚物。用特性粘数[η]、FTIR、1H NMR、DSC、GPC、XRD等测试技术对其结构进行了表征,考察了不同投料比对共聚物的影响。结果表明,当投料比n(LA)∶n(Val)=95∶5时,Mw=7 300,Mn=5 400,共聚物相对分子质量最大,结晶度(13.5%)要比均聚物聚外消旋乳酸(PDLLA)的低。随着投料比中Val含量的增加,共聚物相对分子质量逐渐降低,由结晶态逐渐转变为无定形态。但所得共聚物的Mw均大于1 800,Tg、Tm均与PDLLA的相接近,能够满足生物降解材料在药物缓释领域中的应用。With cheap D,L-Lactic acid （D,L-LA） and valine （Val） as the stanting materials, and SnO as the catalyst, a novel biomaterial, poly（ lactic acid-co-valine）[ P（LA-co-Val） ] , was directly synthesized via melt copolycondensation. The copolymer was characterized with viscosity measurements, FTIR, ^1H NMR, DSC, XRD and GPC. The effects of feed molar ratio were discussed. When the feed molar ratio n（LA） ：n（Val） was 95： 5, the weight-average molecular mass （ Mw ） was 7 300, the number-average molecular mass （ Mn ） was 5 400, which were all the highest. Its crystallinity （13.5%） was lower than that of homopolymer poly （D, L-lactic acid） （PDLLA）. With the increase of the feed molar ratio of Val, Mw of the copolymer P（LA-co-Val） gradually became smaller, and the crystallinity gradually disappeared. But the lowest Mw of 1 800 and the glass-transition temperature （ Tg ） and the melting temperature （ Tm ） of the PDLLA, which Could meet the requests for the application in drug delivery copolymer were similar to that of of this biodegradable material.

关 键 词：外消旋乳酸 缬氨酸 聚(乳酸-缬氨酸)共聚物 生物材料 直接合成 表征 

分 类 号：O629.7[理学—有机化学] O631.5[理学—化学]