Magnesium acrylate induced interfacial compatibilization of EPDM/PP thermoplastic vulcanizate and shape memory behavior

Abstract

The effect of magnesium acrylate (MgMA) on the interfacial compatibility and shape memory behavior of ethylene propylene diene monomer (EPDM)/polypropylene (PP) thermoplastic vulcanizates (TPVs) prepared through peroxide-induced dynamic vulcanization was investigated in this paper. MgMA could react with both PP and EPDM at their phase interface, which improved the EPDM/PP interfacial compatibilization. The PP continuous phase fixed the temporary shape and the crosslinked EPDM particles provided driving force for shape recovery. The improved phase interface played a significant role in the stress transmission between PP and EPDM phases. It is found that the shape fixity ratio (Rf) and the shape recovery ratio (Rr) of TPVs exceeded ∼90% and ∼92.5%, respectively. With the increase of MgMA content, the Rf of TPVs increased firstly and then decreased, while the Rr and recovery rate enhanced in the whole process. Furthermore, the mechanical properties of TPVs were also improved with the increasing MgMA content.