▎ 摘　　要

The influence of the size and content of graphene nanoplatelets (GNPs) on impact fracture toughness of reinforced polypropylene (PP) composites were investigated by means of a pendulum impact instrument at room temperature. The results showed that the Izod V-notched and non-notched impact strength and Charpy V-notched impact strength increased when GNPs weight fraction was <0.4 wt%, and then decreased with increasing GNPs weight fraction. Moreover, the effect of the GNPs size on the impact fracture toughness was relatively significant; the GNPs with large layer number and flake thickness were beneficial to improve the Izod V-notched impact fracture toughness, large particle lateral dimension was beneficial to improve the Izod non-notched impact fracture toughness; while the GNPs with large specific surface area and flake thickness were beneficial to improve the Charpy V-notched impact fracture toughness. Finally, the mechanisms of the toughened and reinforced effects of the GNPs on the PP/composites were discussed. POLYM. COMPOS., 40:E511-E516, 2019. (c) 2018 Society of Plastics Engineers