乳酸基聚酯酰胺聚合物的合成及表征研究  

Study on Synthesis and Characterizaton of Lactic Acid Based Polyester Amide

作　　者：刘荣利[1] 樊国栋[1] 

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

出　　处：《塑料科技》2014年第1期88-92,共5页Plastics Science and Technology

基　　金：陕西省科技攻关项目(2008K07-32);陕西科技大学研究生创新基金项目

摘　　要：以辛酸亚锡和对甲苯磺酸为催化剂,采用梯度升温法,将乳酸(LA)与马来酸酐(MAH)在160℃、压力0.096MPa下直接熔融缩聚得到聚乳酸-马来酸酐共聚物(P(LA/MAH)),再以2,2'-(1,3-亚苯基)-二噁唑啉(1,3-PBO)为扩链剂,扩链得到可生物降解的聚酯酰胺(PEA)。采用乌氏黏度计、FTIR、1H-NMR、DSC、XRD、TGA等测试手段对该聚合物的结构和性能进行了表征。结果表明:扩链反应最佳条件为压力0.096 MPa,温度160℃,羧基和噁唑啉基团的摩尔比n(–COOH):n(–oxazoline)=1:1.6,反应时间20 min;所得PEA的最大黏均摩尔质量(Mη)可达50 097。另外,由于苯环和酰胺基的引入,产物的刚性增强,而且其玻璃化转变温度(Tg)相对于PLA有所提高;其热分解过程为一步分解且热稳定性提高;产物的结晶度仅为0.87%,呈无定形态,其柔韧性比PLA有所增强。First, the carboxyl-terminated lactic acid-maleic anhydride copolymer （P（LAJMAH）） was synthesized via directly melt polycondensation with D,L-lactic acid （D,L-LA） and maleic anhydride （MAH） as raw material, the stannous octoate and p-toluenesulfonic acid as catalyst at the temperature of 160℃ and the pressure of 0.096 MPa by using gradient temperature method. Then, the polyester amide （PEA） was prepared by P（LA/MAH） and 2,2＇-（1,3-phenylene） bis（2-oxazoline） （1,3-PBO） as a chain extender. The effects of the amount of chain extender 1,3-PBO, polymerization temperature and time on the synthesis of lactic acid based PEA were studied. The synthetic products were characterized by FTIR, ~H-NMR, DSC, XRD and TGA. The results demonstrate that the highest viscosity-average molecular weight （M~） of the PEA can achieve 50 097 when the molar ratio of oxazoline and carboxyl end groups, reaction temperature, vacuum degree and reaction time are 1.6/1.0, 160~C, 0.096 MPa and 20 rain, respectively. Compared with PLA, since the introduction of the phenyl ring and amide groups enhance the rigidity of the material, PEA has higher glass-transition temperature （Tg）, moreover, the thermal stability improves and the thermal decomposition is only one step. The crystallinity of PEA is only 0.87% and shows amorphous state, so the flexibility of PEA is better than that of PLA.

关 键 词：聚乳酸-马来酸酐共聚物 二噁唑啉 扩链 直接熔融缩聚 聚酯酰胺 

分 类 号：TQ316.3[化学工程—高聚物工业]