Preparation of polystyrene/SiO₂ nanosphere and its application in toughening PP matrix

SiO₂-g-PS, nano-microspheres, were prepared by grafted styrene monomer on the surface of nano-SiO₂ particles with the emulsion polymerization method, and its surface and morphology were studied by TEM, FTIR, TG and XPS. The results showed that the SiO₂-g-PS nano-microsphere had a structure of sphericity composed of PS and SiO₂ as core and shell respectively. A composite material of SiO₂-g-PS nano-microsphere and polypropylene (PP) was prepared by the melt-blending process and the mechanical performance was investigated. The results showed that the impact and tensile strength of the composite material could be improved obviously when the loading of SiO₂-g-PS nano-microsphere was as low as 4%-6% (mass), and a significant heterogeneous nucleation effect on the crystallization of PP was observed.