effect of elastomer type on spherulitic structure and deformation behavior of isotactic polypropylene

Different types of elastomers are used as toughening agent in polypropylene matrices. the current study has examined spherulitic microstructure and plastic deformation behavior of an isotactic polypropylene (ipp). three different commercial rubber modifiers entitled eoc0.5, eoc5, and poe18 were incorporated in this study. eoc0.5, eoc5, and poe18 are a low molecular weight ethylene-octane copolymer, a high molecular weight ethylene-octane copolymer and a propylene based olefinic elastomer, respectively. compounds including 10 wt% of elastomer phase, along with the ipp were stretched in tension. samples were then examined via transmission optical microscopy. results illustrated that while incorporation of a propylene-based rubber doesn’t affect spherulitic microstructure of ipp that much, ethylene-octane elastomers act as nucleating agents and refine the microstructure significantly. moreover, it was observed that compatibility of the propylene-based rubber particles with the matrix favors crazing in the ipp.