Study of Morphology and Mechanical Properties of In Situ PP/PS Alloy

Abstract

The in situ polypropylene (PP)/polystyrene (PS) alloy was prepared in the presence of dicumyl peroxide (DCP). Purified styrene (St) and pre‐polymerized styrene (PSt), forming a dispersed PS phase in the PP matrix would react with PP matrix to form PP‐g‐PS graft co‐polymers acting as a compatibilizer in these alloys, leading to the formation of in situ PP/PS alloys with in situ compatibilizer during reactive blending in a mixer. The morphology development of the alloy was examined by scanning electron microscopy (SEM) and was described using the characteristic length L and the average characteristic length Lm. The shape of the dispersed PS phase was regular and the distribution of PS particles was uniform. Tensile properties of the alloy were improved with mixing time and fluctuated in a certain composition range.