端羟基聚乳酸共聚物的合成及表征  

Synthesis and Characterization of Hydroxyl-Terminated Poly(Lactic Acid)

作　　者：樊国栋[1] 张春梅[1] 陈春兰[1] 杨锐[1] 李甜甜[1] 

机构地区：[1]教育部轻化工助剂化学与技术重点实验室,陕西科技大学化学与化工学院,陕西西安710021

出　　处：《高分子材料科学与工程》2011年第12期16-19,共4页Polymer Materials Science & Engineering

基　　金：陕西省科技攻关项目(2008K07-32);陕西省教育厅重点实验室重点科研计划项目(09JS061);陕西科技大学研究生创新基金资助

摘　　要：以乳酸为原料,辛酸亚锡为催化剂,采用梯度升温法,在168℃、0.098 MPa下直接熔融缩聚合成端羟基改性聚乳酸共聚物聚(乳酸/1,4丁二醇)[P(LA/BDO)]、聚(乳酸/二乙醇胺)[P(LA/DEA)]和聚(乳酸/ε-己内酯)[P(LA/CL)]。用乌氏黏度法、红外光谱(FT-IR)、核磁共振(1H-NMR)、差示扫描量热(DSC)、热重分析(TGA)及X射线衍射(XRD)等对聚合物进行了表征。结果表明,三种端羟基聚合物的Tg均比PLA的低,改性剂的引入降低了聚乳酸的刚性,起到了一定的增塑作用;各聚合物热稳定性较好,为一步分解;P(LA/CL)和P(LA/BDO)的结晶度比PLA有所降低,柔韧性增强,而P(LA/DEA)为无定型聚合物,这种无定型结构有利于材料的降解。The hydroxyl-terminated modified polylactic acid copolymers of poly（lactic acid/1,4-butanediol）[P（LA/BDO）],poly（lactic acid/diethanolamine）[P（LA/DEA）] and poly（lactic acid/ε-caprolactone）[P（LA/CL）]were synthesized via directly melt polycondensation with D,L-racemic lactic acid（D,L-LA） as raw material and stannous octoate as catalyst.The copolymerization reaction was performed at the temperature of 168 ℃ and the pressure of 0.098 MPa using linear heating method.The copolymers were characterized by viscosity-average molecular weight,Fourier transform infrared spectrum（FT-IR）,1H nuclear magnetic resonance spectrum（1H-NMR）,differential scanning calorimetry（DSC）,thermogravimetric analysis（TGA） and X-ray diffraction（XRD）.The results demonstrate that Tg of the hydroxyl-terminated copolymers is lower than that of PLA,reducing the rigidity of PLA with certain plasticization;The copolymers have good thermal stability for one-step decomposition;Compared with PLA,the crystallinity of P（LA/CL） and P（LA/BDO） decreases,and the flexibility increases.While P（LA/DEA） is amorphous polymer,this amorphous structure is conducive to the degradation.

关 键 词：聚乳酸 端羟基改性 梯度升温 直接熔融缩聚 

分 类 号：TQ316.42[化学工程—高聚物工业]