Change in the properties of impact polystyrene during multiple processing

Abstract

It has been shown experimentally that the multiple extrusion of grade UP-1E impact polystyrene (5–7 cycles) has almost no effect on most of the physicomechanical properties, the content of volatiles and helium or the residual monomer content. Multiple processing of the same polystyrene by injection molding (10 cycles) causes partial degradation of the material and the destruction of its crosslinked fraction, which results in increased fluidity, reduced molecular weight, and a partial improvement in mechanical properties (approximately up to the fifth or sixth cycle).