增容高抗冲聚苯乙烯/高乙烯基聚丁二烯橡胶热塑性硫化胶的形态演变及增容机制

Morphology Evolution and Compatibilizing Mechanism of Compatibilized HIPS/HVPBR TPV

采用动态硫化法制备苯乙烯-丁二烯-苯乙烯(SBS)增容高抗冲聚苯乙烯(HIPS)/高乙烯基聚丁二烯橡胶(HVPBR)热塑性硫化胶(TPV),通过场发射扫描电子显微镜观察动态硫化过程中橡胶相的形态演变,研究增容剂SBS对TPV微观相态结构的影响并探讨其增容机制。结果表明:随着硫化时间延长,SBS增容TPV中橡胶粒子粒径减小;硫化时间为6 min左右,橡胶粒子呈类球状均匀分散于树脂相中,且粒径为3~5μm;与未增容TPV相比,SBS增容TPV中橡胶粒子表面粗糙,形态均一,粒径较小;在剪切力作用下,SBS增容TPV中橡胶粒子表面形成纳米级杂乱的层叠式结构,从而增强了其与树脂相的界面作用力,提高了TPV的物理性能。

The SBS block copolymer compatibilized HIPS/HVPBR TPV was prepared by the dynamic vulcanization method. The morphology evolution of rubber phase during the dynamic curing process was observed by field emission scanning electron microscope. The effect of compatibilizer SBS on the microstructure of TPV was investigated and its compatibilizing mechanism was discussed. The results showed that,the size of rubber particles in SBS compatibilized TPV was decreased with extended curing time,and when the curing time was about 6 min,the rubber particles were spherical and dispersed in the resin phase with the size of 3-5 μm. Compared with the uncompatibilized TPV,the rubber particles in SBS compatibilized TPV showed rougher surface,more uniform shape and smaller size. Under shearing force,nano-level disordered and stacked structure on the surface of rubber particles in SBS compatibilized TPV was formed,which enhanced the interfacial interaction between rubber particles and resin phase and improved the physical properties of TPV.