二元羧酸单酯金属盐对PVC的热稳定作用——性能递变规律与机理  

Heat-stabilizing Effect of Dicarboxylic Acid Monoester Metal Salts on PVC-Law and Mechanism of Performance Evolution

作　　者：曹先贵 吴茂英[1] 刘辉 CAO Xiangui;WU Maoying;LIU Hui(School of Chemical Engineering and Light Industry,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]广东工业大学轻工化工学院,广州510006

出　　处：《中国塑料》2018年第7期116-121,共6页China Plastics

摘　　要：用烘箱变色法测试了丙二酸、丁二酸和马来酸单丁酯的钙、锶、钡、锌和镉盐对聚氯乙烯(PVC)热稳定性的影响。结果表明,二元羧酸单酯金属盐所稳定PVC的变色随其分子中羧酸根羰基C原子的正电性和金属离子的极化力的增强而减慢,而分子中含有亲双烯结构的二元羧酸单酯金属盐所稳定的PVC的着色减轻;据此可以推知,二元羧酸单酯金属盐之所以能抑制PVC的变色,并不是因为能取代不稳定氯(Frye和Horst机理),而是因为能以羧酸根羰基C原子和金属离子与PVC发生亲电反应,而之所以分子中含有亲双烯结构的二元羧酸单酯金属盐所稳定的PVC着色减轻,则是因为它们还能与PVC发生Diels-Alder环加成反应。The effects of calcium,strontium,barium,zinc and cadmium salts of monobutyl malonate,succinate and maleate on the heat stability of poly(vinyl chloride)(PVC)were determined by an oven discoloration method.The results indicated that the discoloration rate of PVC stabilized with dicarboxylic acid monoester metal salts decreased with an increase of the positive electricity of carbon atom in carbonyl groups and the polarization force of metal ions in the molecules.However,PVC stabilized with dicarboxylic acid monoester metal salt containing a dienophilic structure presented a weaker coloring effect.It was deduced that the reduction mechanism of discoloration rate for PVC by dicarboxylic acid monoester metal salts was attributed to the electrophilic reactions of carbon atom in carbonyl groups and metal ions with PVC.Moreover,the Diels-Alder cycloaddition reaction led to the weak coloring effect on PVC when stabilized with dicarboxylic acid monoester metal salt containing a dienophilic structure.

关 键 词：二元羧酸单酯金属盐 聚氯乙烯 热稳定作用 性能递变规律 机理 

分 类 号：TQ325.3[化学工程—合成树脂塑料工业]