聚柠檬酸13,-丙二醇酯的合成及降解

Synthesis and Hydrolytic Degradation of Poly (1,3-propanediol-citrate acid)

在无催化剂的条件下,以柠檬酸与13,-丙二醇熔融聚合反应,生成了具有高度交联的聚酯化合物。考察了反应温度、真空度和醇酸比对聚酯合成的影响。用傅里叶红外光谱对产物进行了结构分析,并研究了其在不同pH值溶液中体外降解性能。结果表明,合适的反应条件为:反应温度为145℃,真空度为0.07 MPa,醇酸物质的量比为1.5∶1;在pH值为1.0的盐酸溶液,pH值为7的蒸馏水和pH值为7.4的磷酸盐缓冲溶液中,进行体外降解实验,结果表明,该聚酯在磷酸盐缓冲溶液中浸泡227 h后,吸水率可达1 000%以上,失重率仅为25%～30%;而在盐酸溶液中,失重率可到70%以上。

A new kind of highly cross-linked poly（diol citrates） based on trifunctional citrate acid and 1,3-PDO was synthesized by melt polycondensation.The reaction conditions,such as reaction temperature,vacuum degree and mole ratio of alcohol and acid were investigated.The obtained copolymers were characterized by Fourier transform infrared spectroscopy.In vitro degradation was carried out in phosphate buffer saline（pH=7.4） or hydrochloric acid（pH=1.0） or distilled water.The results showed that the better reaction temperature was 145℃,the vacuum degree was 0.07 MPa,and the molar ratio of alcohol and acid was 1.5∶1.In vitro degradation experiments showed that by immerging the polymer in phosphate buffer solution for 227h,the water adsorption（absorption）was up to 1000% and the mass loss was 25% ~ 30%.While immerging in hydrochliric acid,the weight loss was 70%.