Reaction injection molding : analyzing the filling stage of a complex product with a highly viscous thermoset

Although numerical simulation has proved to be a useful tool to predict the filling behavior of injection molding products, few applications in reaction injection molding (RIM) have been reported. This is mainly due to the lack of appropriate descriptions of the material behavior, and to the lack of accurate material data. The analysis of the filling stage of the RIM process requires the determination of the cure kinetics and the rheological, pvT, and thermal behavior of the material, which in this study is a highly filled copolymer of ethylene and vinyl-acetate (EVA). Since this copolymer yields some viscosity anomalies, due to the amount of filler, the rheology of a similar EVA compound with low filler content was also investigated. The viscosity of this compound can be described by a Carreau model at low conversions levels (