High mechanical and tribological performance polyimide nanocomposites using amine-functionalized graphene nanosheets

The novel polyimide (PI) nanocomposites that possess outstanding strength and high tribological performance were fabricated using different contents of amine-functionalized graphene nanosheets (AGNS) via in-situ polymerization. The AGNS was successfully prepared by condensation reaction and nitroreduction. Compared with properties of pure PI or PI/graphene nanosheets (GNS) blends, PI/AGNS nanocomposites exhibit distinguished improvement on thermal stability, mechanical properties and tribological performance due to the strong covalent bonds between AGNS and PI. Especially, PI/AGNS-0.5wt% nanocomposites revealed the extraordinary tribological properties as friction coefficient and wear rate decreased by 41.9% and 76.2% under dry sliding condition, respectively. The resultant PI/AGNS nanocomposites owned the combined excellent tribological and mechanical properties, demonstrating their potential applications in wear-resistant materials and other high-performance areas.