Graphene modified PVDF high-performance composite membrane and preparation method thereof

The invention discloses a graphene modified PVDF high-performance composite membrane and a preparation method thereof. The graphene modified PVDF high-performance composite membrane comprises, by mass, 0.5-5% of graphene, 10-30% of PVDF, 2-8% of N-methyl pyrrolidone (NMP), 40-60% of an organic solvent and 5-20% of a pore-foaming agent. Graphene and PVDF are grafted through covalent bonds, so that the structure is stable, the stability of the high-performance composite membrane is ensured, and the mechanical strength of the high-performance composite membrane is enhanced; designed graphene and a pore-foaming agent are grafted through hydroxyl and carboxyl, the structure is loose, the pore-foaming agent more conveniently falls into a coagulating bath, it is ensured that the pore diameter of the high-performance composite membrane is uniform, and the high-performance composite membrane has high water flux; and according to the designed graphene modified PVDF high-performance composite membrane, graphene can be i