丙烯酸酯乳液在氯乙烯悬浮聚合体系中稳态原位增韧改性

In Situ Toughening Modification of Polyvinyl Chloride Resin by Acrylate Emulsion at Steady-State in the Process of Vinyl Chloride Suspension Polymerization

以丙烯酸丁酯(BA)、丙烯酸乙酯(EA)为单体,通过乳液聚合制备了粒径100 nm左右的均相交联共聚乳液(AC),并将其作为氯乙烯悬浮聚合用接枝改性剂,原位接枝共聚和原位共混进行增韧改性,以制备高抗冲复合聚氯乙烯树脂(AC-PVC)。研究了乳化剂种类和EA用量对AC乳液稳定性及乳胶粒粒径的影响,模拟了AC乳液在三氯乙烯悬浮聚合体系中的稳定性,并在20 L高压反应釜中进行了氯乙烯悬浮聚合试验,对不同分散剂用量下所得AC-PVC颗粒形态及力学性能进行了表征。结果表明,反应釜粘釜现象明显改善,粗粒径的AC-PVC比例降低,且AC-PVC的抗冲性能显著提高,最高缺口冲击强度可达普通SG-5型PVC树脂的27倍。

A stable homogeneous cross-linked copolymer emulsion(AC)with 100 nm diameter was prepared by emulsion polymerization with butyl acrylate(BA)and ethyl acrylate(EA)as monomers.Thereafter,high impact polyvinyl chloride resin(AC-PVC)can be gotten if the above AC can be used as toughening modifier in vinyl chloride(VC)suspension polymerization system because of in situ graft copolymerization and in situ blending coexist.It was difficult to watch the stability of VC suspension polymerization with AC emulsion in a 20 L high pressure reactor,so trichloroethylene suspension polymerization system was simulated at first.Effects of emulsifier kinds,EA dosage,amount of dispersion agent on particle size of AC and AC-PVC properties were studied.Results show that autoclave sticking was obviously weakened,and the proportion of coarse size of AC-PVC is reduced,but the impact resistance of AC-PVC is significantly improved.The maximum notch impact strength of AC-PVC is 27 times higher than that of SG-5 PVC resin.