▎ 摘　　要

NOVELTY - Bottom polyurea protective coating comprises component A and B in volume ratio 1:2- 4. The component A comprises isocyanate, polysulfide-modified epoxy resin and diluent and component B comprises aliphatic synthetic hindered amine polyurea resin, coloring pigment, filler, graphene slurry, organic zinc, dispersant, ultraviolet light absorber, ultraviolet light stabilizer, anti-settling agent, leveling agent, antifoaming agent, matting powder and solvent. USE - The bottom polyurea protective coating is useful for car chassis system (claimed). ADVANTAGE - The coating has film thickness of over 80 mu m, fast drying speed, high construction effect, strong adhesion, resistance to good impact, aging and salt and is environmentally friendly. The preparation method is simple and economical. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing bottom polyurea protective coating, comprising (i) adding isocyanate and polysulfide modified epoxy resin into reaction kettle, heating uniformly, stirring until the mass percentage of isocyanates reaches to 11-19%, cooling, adding diluent and stirring to obtain component A; (ii) mixing part of aliphatic synthetic hindered amine polyurea resin with colored pigment, filler, organic zinc, dispersant, anti-settling agent, defoaming agent and partial solvent, grinding into slurry, adding slurry into remaining aliphatic synthetic hindered amine polyurea resin, graphene slurry, ultraviolet absorbers, ultraviolet stabilizers, leveling agent, matting powder and remaining solvent, mixing and filtering to obtain component B;and (iii) mixing component A and B in volume ratio 1: 2-4.