The effects of cooling medium temperatures and plastic/rubber ratios on solidification and crystallization kinetics of dynamically-vulcanized polypropylene/ethylene-propylene-diene rubber (PP/EPDM) blends were investigated with the aid of an in-situ measurement technique. The cooling medium temperature heavily influenced the solidification kinetics primarily due to a combination of latent heat liberated from the molten polymer and the heat transferred away via the metallic wall during the cooling period. Interestingly, the parameter C in three-parameter model was not only affected by the material properties, but also by the cooling condition, different from the previous literature. The crystallization kinetics analysis indicated that the effect of EPDM in the blends consisted of both nucleation-promoting effect (low EPDM loading) and steric effect (higher EPDM loading). The present kinetic analysis may be helpful to further studies on improving the product performances for industrial applications.

Keywords: dynamic vulcanization; PP/EPDM blends; solidification kinetics; crystallization kinetics; cooling medium temperature