C_(22)-环脂三酸酯等三类增塑剂结构与性能关系研究

Study on the relationship between structures and properties of C_(22)-cycloaliphatic tricarboxylic acid esters and other two kinds of plasticizers

测定了C22-环脂三酸酯、邻苯二甲酸酯和马来酸酯等三类增塑剂的若干理化性能及其增塑的聚氯乙烯(PVC)材料的力学性能、电性能和热性能。研究了三类增塑剂结构母体和甲酸酯基(—COOR)中烷基R对增塑剂性能的影响。结果表明,三类增塑剂的密度均随着烷基R链长的增加而减小;与邻苯二甲酸酯、马来酸酯不同,C22-环脂三酸酯的运动粘度随着烷基R链长的增加而减小;C22-环脂三酸酯的闪点和耐热性能远高于邻苯二甲酸酯和马来酸酯,其加热减量则远低于后两者。C22-环脂三酸酯类增塑剂,烷基R较短时塑化性能弱,过长则与PVC相容性变差,无法成膜。三类增塑剂增塑的PVC材料的表面电阻率均随着烷基R链长的增加而增加。烷基R相同时,表面电阻率大小顺序为:C22-环脂三酸酯>邻苯二甲酸酯>马来酸酯。C22-环脂三酸酯增塑的PVC材料的抗热老化性能优于邻苯二甲酸酯和马来酸酯增塑的PVC材料。

Several physicochemical properties of C 22-cycloaliphatic tricarboxylic acid esters ,phthalates and maleic acid esters were measured , the mechanical , electrical and thermal properties of their plasticized PVC materials were also studied .The influence of plasticizer structure and alkyl R in the formic acid ester on plasticizer properties was investigated .The result showed that the densities of the three kinds of plasti-cizers decrease with increasing the chain length of the alkyl R .The kinematic viscosity of C 22-cy-cloaliphatic tricarboxylic acid esters also decreases with increasing the chain length of the alkyl R ,which is different from those of phthalates and maleic acid esters .Furthermore, the flash point of C22-cy-cloaliphatic tricarboxylic acid esters are much higher than those of phthalates and maleic acid esters ,and the heating loss of the former is far below the latter two esters .With regard to C22-cycloaliphatic tricarbox-ylic acid esters ,a shorter alkyl R results in a weaker plasticizing performance ,while a much longer alkyl R may lead to a poor compatibility with PVC ,and the membrane cannot be formed ultimately .The surface resistance rates of the PVC materials plasticized by the three kinds of plasticizers increase with the in -crease of the length of alkyl R .For the same alkyl R ,their surface resistance rates can be arranged in the following order：C22-cycloaliphatic tricarboxylic acid esters 〉phthalates ester 〉maleic acid ester .The heat aging resistance of the PVC material plasticized by C 22-cycloaliphatic tricarboxylic acid esters is higher than those plasticized by phthalates and maleic acid esters .