▎ 摘　　要

NOVELTY - Light broadband efficient electromagnetic shielding coating comprises component A and component B. The component A includes 60-70 pts. wt. epoxy resin, 0.5-1 pts. wt. graphene and magnesium oxide mixed powder, 15-20 pts. wt. silver-coated copper powder, 0.5-1 pts. wt. auxiliary agent, 0.5-1 pts. wt. coupling agent, and 5-7 pts. wt. solvent. The component B includes 20-30 pts. wt. amine curing agent. The graphene and magnesium oxide mixed powder is a mixed product obtained through a combustion synthesis reaction, and the combustion synthesis reaction comprises (1) mixing nano-magnesium oxide powder and magnesium powder, and placing in the reactor, (2) evacuating inside of reactor and filling with carbon dioxide gas, (3) heating reactant and igniting by tungsten wire, and initiating the combustion synthesis reaction of magnesium powder and carbon dioxide, and (4) directly pulverizing the combustion synthesis product to obtain the graphene and the magnesium oxide mixed powder, USE - he electromagnetic shielding coating is useful in electronic information industry, communication device and electronic product. Can also be used in aerospace field. ADVANTAGE - The electromagnetic shielding coating has low volume of conductive filler, shielding efficiency of greater than or equal to 65dB (150MHz to 10GHz), electrical conductivity of square resistance of less than or equal to 400 mOmega, and surface density of less than or equal to 90g/m2; and realizes the coordination and unity of high shielding efficiency, electrical conductivity, low density and construction technology of the coating. DETAILED DESCRIPTION - Light broadband efficient electromagnetic shielding coating comprises component A and component B. The component A includes 60-70 pts. wt. epoxy resin, 0.5-1 pts. wt. graphene and magnesium oxide mixed powder, 15-20 pts. wt. silver-coated copper powder, 0.5-1 pts. wt. auxiliary agent, 0.5-1 pts. wt. coupling agent, and 5-7 pts. wt. solvent. The component B includes 20-30 pts. wt. amine curing agent. The graphene and magnesium oxide mixed powder is a mixed product obtained through a combustion synthesis reaction, and the combustion synthesis reaction comprises (1) mixing the nano-magnesium oxide powder and magnesium powder with a mass ratio of 80-86:10-15 to obtain a reactant, and is placing in the reactor, (2) evacuating inside of reactor and filling with carbon dioxide gas, where the pressure of carbon dioxide gas is 0.5-1MPa, (3) heating reactant and igniting by tungsten wire, and initiating the combustion synthesis reaction of magnesium powder and carbon dioxide, and (4) directly pulverizing the combustion synthesis product to obtain the graphene and the magnesium oxide mixed powder, where the graphene and the magnesium oxide mixed powder comprise the nano-magnesium oxide powder of the dilution effect in the reactant. An INDEPENDENT CLAIM is also included for a method for preparing electromagnetic shielding coating comprising placing 60-70 pts. wt. epoxy resin, 0.5-1 pts. wt. graphene and magnesium oxide powder, 15-20 pts. wt. silver-coated copper powder, 0.5 to 1 pts. wt. auxiliary agent, 0.5 to 1 pts. wt. coupling agent, and 5-7 pts. wt. solvent in a container and mixing evenly to obtain component A, providing 20-30 pts. wt. amine curing agent as B component, and uniformly mixing the component A and the component B when using.