相形态对聚合物反应共混过程的影响

通过采用典型的热力学不相容共混体系聚烯烃弹性体/聚苯乙烯(POE/PS),利用流变学和形态研究的方法,考察了不同相形态(海岛结构和双连续结构)对聚合物反应共混过程的影响.研究发现相形态对聚合物原位增容共混反应有显著的影响,界面反应的进程与界面形态的变化能力直接相关.对于双连续结构的共混物,其形态稳定性最差,因而最有利于界面反应的发生;而在海岛结构的共混体系中,界面反应的进程则取决于界面变形的难易程度,黏度比小的体系更容易发生界面反应。

EFFECT OF PHASE MORPHOLOGY ON THE REACTIVE BLENDING

The updating process of interface plays an important role in the polymer reactive blending process,including the changes of interfacial area and phase morphology,and the material transportation.In this article,by using a typical thermodynamic incompatible blending system,polyolefin elastomer/polystyrene,the influence of different morphology (sea\|island structure and co-continuous structure) on the polymer reactive blending processes was investigated by means of rheology and morphology analyses.Rheological analysis suggests the additional contribution of formed block copolymer in the reactive blends,as well as the variation of relaxation process of droplets in sea\|island blend.The conversion in a typical blend is analyzed based on the change of interfacial relaxation time and droplet size by using the mean field theory.It is then suggested that phase morphology has a significant influence on the polymer reactive blending processes.Interfacial reactions happen more easily in blends with co\|continuous morphology due to their weak stability,while in the blends with the sea\|island morphology,the interface reaction process depends on the ease of interface deformation,and the blends system with small viscosity ratio favors interfacial reactions.