▎ 摘　　要

NOVELTY - A metal surface treating agent comprises 0.01-0.1 %mass functionalized graphene, 15-25 %mass organic resin, 0-0.6 %mass inorganic corrosion inhibitor, appropriate amount of pH adjusting agent and remaining deionized water. The organic resin is acrylate emulsion, aqueous polyurethane resin and/or aqueous organosiloxane modified resin. The inorganic corrosion inhibitor is a vanadate, molybdate and/or phytic acid. The pH adjusting agent is acetic acid or aqueous ammonia. The functionalized graphene is a styrene-maleic anhydride copolymer functionalized graphene aqueous dispersion. USE - Graphene composite type aqueous metal surface treating agent for protective film. ADVANTAGE - The styrene-maleic anhydride copolymer has excellent water dispersion stability, unique lamellar structure, large surface area and surface functional groups, and can be combined with organic resin and inorganic corrosion inhibitor in the metal surface to form a layer of excellent corrosion resistance of the protective film. DETAILED DESCRIPTION - A graphene composite type aqueous metal surface treating agent comprises 0.01-0.1 %mass functionalized graphene, 15-25 %mass organic resin, 0-0.6 %mass inorganic corrosion inhibitor, appropriate amount of pH adjusting agent and remaining deionized water. The surface treatment agent has a pH of 5-8. The organic resin is acrylate emulsion, aqueous polyurethane resin and/or aqueous organosiloxane modified resin. The inorganic corrosion inhibitor is a vanadate, molybdate and/or phytic acid. The pH adjusting agent is acetic acid or aqueous ammonia. The functionalized graphene is a styrene-maleic anhydride copolymer functionalized graphene aqueous dispersion. The styrene-maleic anhydride copolymer functionalized graphene aqueous dispersion is prepared by dispersing styrene-maleic anhydride copolymer in an aqueous solution, adjusting the pH of the solution to 9-11 by sodium hydroxide, stirring at 90 degrees C for 4 hours until the solution is to be transparent, cooling to room temperature to obtain electrolytic solution, where the mass ratio of styrene-maleic anhydride copolymer to the solution is 0.1-0.5%, (ii) using high purity graphite rod as cathode and anode, placing in the electrolytic solution, performing electrolysis under direct current power supply of 5-20 V constant voltage to obtain black functionalized graphene aqueous dispersion, (iii) adjusting the pH of the aqueous dispersion to 7-9 with aqueous ammonia, ultrasonically dispersing in ultrasonic disperser for 1-2 hours, and centrifuging to remove large aggregates in low-speed centrifuge to obtain styrene-maleic anhydride copolymer functionalized graphene aqueous dispersion.