Dynamic Vulcanization of Thermoplastic Elastomers Based on Poly(Epichlorohydrin-Co-Ethylene Oxide) and Polypropylene

Summary

Unvulcanized and dynamically vulcanized blends of poly(epichlorohydrin-co-ethylene oxide) elastomer and polypropylene have been prepared by melt mixing in an internal mixer. The solvent resistance, morphology, dynamic mechanical and mechanical properties of these blends were studied with special reference to the effect of the crosslinking agent content. The swelling behaviour shows that the blends, with and without dynamic vulcanization, present excellent resistance to solvents ASTM A, B, C and D, at room temperature. Morphology study by scanning electron microscopy of the cryofractured surface and analysis of the dynamic mechanical properties of the system indicate that the uncrosslinked blend is immiscible and form a two-phase structure, where the rubber phase was dispersed as domains in the continuous polypropylene matrix. The mechanical properties of the crosslinked blends do not improve by increasing the doses of crosslinking agent.