甘油基聚酯PVC增塑剂的制备及应用研究

Study on Preparation and Application of PVC Polyester Plasticizer Originated from Glycerol

以甘油、六氢苯酐为原料,钛酸四正丁酯为催化剂,2-乙基己醇为封端剂,环己烷为带水剂,经脱水缩聚、减压蒸馏制备聚六氢苯酐甘油酯。探究实验得到合成聚六氢苯酐甘油酯的佳醇酸摩尔比、催化剂和封端剂用量。通过红外光谱分析(FTIR)、热重分析(TG)、高效凝胶色谱分析(GPC)等对聚酯的结构、热稳定性及平均分子量进行了表征,并将该聚酯加入到聚氯乙烯(PVC)中,按照定配方制得PVC试片。结果表明:佳反应条件是六氢苯酐、甘油的摩尔比为1.0:1.4,2-乙基己醇、六氢苯酐的的摩尔比为0.8:1.0,催化剂用量为甘油、六氢苯酐和2-乙基己醇总量的1.0%;产品酸值在1.55 mgKOH/g左右,平均分子量在4 500左右,酯化率达到99.6%;产品呈淡黄色,热稳定性良好;制得PVC试片的拉伸性能和热稳定性较高,聚酯的迁移率较低。

Poly hexahydrophthalic anhydride glyceride was synthesized by a polycondensation reaction and reduced pressure distillation with tetra-n-butyl titanate as the catalyst, cyclohexane as dehydrating agent, 2-ethyl-hexanol as capping agent, glycerinum and hexahydrophthalic as raw material. The influence factors including the molar ratio of acid anhydride and diol, the dosage of catalyst and capping agent on the polyester products were examined. The characterization was conducted by FTIR, TG, and gel permeation chromatography（GPC）, then put a certain amount of products into the polyvinyl chloride （PVC） to make them to be PVC plastic specimen. Optimum conditions are as follows： the molar ratio of acid anhydride and diol is 1.0：1.4, the molar ratio of 2-ethyl hexanol and hexahydrobenzene is 0.8：1.0, catalyst content is 1.0% of total alcohol acid mass. The product acid value is around 1.55 mgKOH/g, average molecular weight is around 4 500, esterification yield can reach to 99.6%. The product has good thermal stability, and the specimens of PVC get good tensile properties, thermal stability and low mobility.