Abstract:Graphene was prepared by Hummers method. The surface of graphene was grafted with titanium dioxide to obtain graphene grafted TiO2 (RGO-TiO2) nanocomposites. The RGO-TiO2/PP composite was prepared by melt-mixing polypropylene (PP) with the hybrid. FT-IR, XRD, Raman and SEM were used to characterize the microstructure of composites. Thermogravimetric analysis (TGA), limiting oxygen index (LOI), vertical combustion method and cone calorimeter were used to study the thermal performance and combustion behavior of the composites. The results show that RGO-TiO2 is more dispersible than GNS in the composite system. The mechanical properties of the composites were studied by universal testing machine and impact testing machine. A small amount of RGO-TiO2 can improve the thermal stability of the composites, increase the LOI by 20.6%, decrease the fusion dripping rate and the amount of smoke in the vertical combustion. The heat release rate (HRR) and the peak heat release rate (PHRR) decrease by 10% and 43.8%, respectively, and with the increase of the RGO-TiO2 content, the flame retardancy of the composites is improved. Bending strength and impact strength are increased and then decreased.