氯乙烯/N-苯基马来酰亚胺共聚物组成控制和优化

CONTROL AND OPTIMIZATION FOR VINYL CHLORIDE/N- PHENYLMALEIMIDE COPOLYMER COMPOSITION

研究了氯乙烯 /N 苯基马来酰亚胺 (VC/PMI)共聚物组成随转化率的变化 ,体系中共聚物的累积组成偏差小于 0 0 5或 0 1的单体配比范围很小 ,采用加入第三单体丙烯腈 (AN)的方法进行改善 ,并以PMI在共聚物中的累积组成偏差作为控制参数 ,得到了PMI在共聚物中的累积组成偏差小于 0 0 5和 0 1的VC/PMIlAN较优的配比范围 .结合悬浮聚合工艺的特点 ,确定了VC/PMI/AN悬浮共聚的最佳单体配比范围为f1=0 72～ 0 84 ,f2 =0 0 2～ 0 0 4 ,f3 =0 1 2～ 0 2 4 .

N-phenylmaleimide(PMI)is used to copolymerize with vinyl chloride (VC) for improving the heat resistance of PVC,but the instantaneous and integral copolymer compostition varies greatly with conversion for vinyl chloride/N-phenylmaleimide copolymerization systems.The recurrence method deduced from Mayo\|Lewis equation was applied to investigate quantitatively the variations of copolymer compositions wtih conversion for VC/PMI suspension copolymerization.The copolymer compositions can be controlled and optimized by means of selecting a third monomer and its content.For VC/PMI suspension copolymerization,acrylonitrile (AN) was preferably selected to improve copolymer composition homogeneity in order to improve heat resistance and other properties.The ranges of monomer feed fraction with the copolymer composition error of PMI lower than 0 05 ot 0 1 was gained,which could direct the study on VC/PMI/AN suspension terpolymerization.On the basis of the prediction,control and optimization of the copolymer composition variation with conversion and the features of the polymerization technology,the optimum region of monomer feed fraction for VC/PMI/AN suspension terpolymerization was obtained.