有机锡参与合成P(BA-EHA)/PVC及共混改性PVC的结构与性能

通过种子乳液聚合方法,采用丙烯酸丁酯(BA)、丙烯酸2-乙基己酯(EHA)为核层单体,与少量有机锡单体共聚制备了含有机锡的P(BA-EHA)胶乳,与氯乙烯(VC)乳液接枝共聚合成了P(BA-EHA)/PVC复合改性剂。通过透射电子显微镜(TEM)、动态力学分析仪(DMA)、扫描电子显微镜(SEM)等测试手段,考察了复合乳胶粒子和共混材料的形态结构、复合改性剂中有机锡含量对其共混改性PVC材料的力学性能及复合粒子热稳定性的影响。DMA和TEM分析结果表明:复合粒子的加入显著改善了橡胶相与PVC之间的相容性,P(BA-EHA)在PVC基体中具有很好的分散性和均匀度,SEM照片显示共混材料缺口断面表现为优异的基体屈服型断裂韧性。

Synthesis of P(BA-EHA)/PVC in the presence of organotin and the structure and property of blending modified PVC

P(BA-EHA)latex containing organotin was synthesized by seeding emulsion polymerization,in which butyl acrylate(BA) and 2-ethylhexylacrylate(EHA) played as core monomer and copolymerized with a small amount of organotin.Then,P(BA-EHA)/PVC blending modifier was synthesized through the copolymerization of P(BA-EHA) with vinyl chloride(VC).The morphological structure of complex latex particle and blends,influences of organotin contents in blending modifier on the mechanical properties of blending modified PVC and the heat stability of composite particles were investigated by transmission electron microscope(TEM),dynamic mechanics analyzer(DMA)and scanning electron microscope(SEM).The results obtained from DMA and TEM showed that the compatibility of rubber phase with PVC was obviously improved with the addition of composite particles,good dispersity and homogeneity were obtained for P(BA-EHA) in PVC.The SEM photoes showed that the notched cross section of blending materials had excellent matrix yielding type of fracture toughness.