酪氨酸改性聚乳酸共聚物的合成及降解研究  

Synthesis and degradation of poly(lactic acid-co-L-tyrosine)

作　　者：白晓丹[1] 樊国栋[1] 李甜甜[1] 林振宇[2] 

机构地区：[1]陕西科技大学教育部轻化工助剂化学与技术重点实验室,西安710021 [2]福州大学食品安全分析与检测技术教育部重点实验室,福州350002

出　　处：《化工新型材料》2012年第1期62-65,共4页New Chemical Materials

基　　金：陕西省科技攻关项目(2008K07-32);食品安全分析与检测技术教育部重点实验室(福州大学)开放基金资助项目(FS10003);陕西科技大学研究生创新基金资助

摘　　要：以乳酸(D,L-LA)和L-酪氨酸(Tyr)为原料[n(D,L-LA)/n(Tyr)=95/5],氯化亚锡(Sn(cl)2)为催化剂,采用梯度升温法,通过直接熔融缩聚合成聚(乳酸-酪氨酸)共聚物(PLA-co-Tyr)。用特性粘度测试、FT-IR、1 H-NMR、GPC、DSC、XRD、TG等对其进行表征,通过SEM、XRD等方法研究了降解前后材料的表面形态、结晶度及失重率的变化。结果表明:系列共聚物中的重均相对分子量Mw最大可达2900,与聚乳酸相比具有较小的Tg和结晶度,分解温度高于180℃,具有良好热稳定性且降解性能优于聚乳酸。Based on the fact that the polylactic acid（PLA） has high crystallinity,poor hydrophilicity and theirs degradation are difficult,tyrosine could be introduced in the chain of the polylactic acid.The new poly（lactic acid-co-L-tyrosine） copolymers（PLA-co-Tyr） were synthesized via directly melt polycondensation with lactic acid（D,L-LA） and L-tyrosine（Tyr） as raw material,and Sn（Cl）2 as catalyst,using linear heating method.The copolymers were characterized by viscosity-average molecular weight,FT-IR,1H-NMR,GPC,DSC,XRD and TG.The degradation experiment of PLA-co-Tyr was carried out in phosphate buffer solution（PBS） at 37℃,using PLA as the control sample.scan electronic microscope（SEM） and XRD were used to analyze the results of degradation.The results demonstrated that the biggest weight average molecular weight of PLA-co-Tyr was 2900.Compared with PLA,it had lower Tg and lower crystallinity.Its decomposition temperature was more than 180℃.The copolymer had good thermal stability and superior performance degradation.

关 键 词：聚乳酸 L-酪氨酸 直接熔融缩聚 梯度升温法 体外降解 

分 类 号：O631.3[理学—高分子化学]