Research Progress in the Toughening and Strengthening of Polypropylene via Inorganic Rigid Particles

The works in toughening and strengthening of polypropylene via inorganic rigid particles were reviewed. The effect of morphology of the filling system, the particle size and distribution, and modifier on the toughening were summarized. It was extensively reported that excellent toughening resulted from a core-shell structure generated by encapsulating rigid particles with elastomer. Sophisticated analysis of PP toughening was discussed,including the criterion of critical matrix ligament thickness, the criterion of interface adhesion, finite element analysis, the transition from debonding to the cavitation/crazing and the cavitation/shear yielding. The hybrid toughening using elastomer and rigid inorganic particles was also mentioned.