▎ 摘　　要

NOVELTY - Double-coating powder coating comprises an inner layer and a surface layer. The surface layer is on the surface of the base material. The inner layer is covered on the surface of the surface layer. The inner layer comprises 65-70 pts. wt. epoxy resin KD2012H, 1-3 pts. wt. ethyltriphenylphosphonium bromide, 2-2.8 pts. wt. stearic acid, 2-4 pts. wt. silicon micro powder, 1-2 pts. wt. graphene and 6-7 pts. wt. curing agent. The surface layer comprises 50-65 pts. wt. polyester resin, 1-4 pts. wt. pigment, 12-20 pts. wt. calcium carbonate, 10-18 pts. wt. graft polymer and 1-1.5 pts. wt. inorganic antibacterial agent. USE - Used as double-coating powder coating. ADVANTAGE - The double-coating powder coating: can prolong the service life and better applied in various environments; and has higher adhesion, so that the surface layer and the substrate can be better and the inner layer is relatively poor in corrosion resistance, so the covering of the surface layer can prevent the inner layer from directly contacting external corrosion factors. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing double-coating powder coating, comprising (i) taking epoxy resin KD2012H, ethyltriphenylphosphonium bromide, stearic acid, silicon micropowder, graphene and curing agent, adding into the high-speed mixer successively, mixing, adding it into the twin-screw extruder, carrying out melt extrusion, slicing, pulverizing, grinding, and sieving to obtain the inner layer powder, where the temperature setting of each zone of the twin-screw extruder is the temperature of the first zone is 120℃, the temperature of the second zone is 125℃, the temperature of the third zone is 125℃, the temperature of the fourth zone is 120℃, the temperature of the fifth zone is 120℃, and the temperature of the machine head is 122℃ and the main engine speed of the twin-screw extruder is 90 revolutions/minute; (ii) taking polyester resin, pigment, calcium carbonate, graft polymer, and inorganic antibacterial agent, adding them into a high-speed mixer in turn for mixing, adding them into a twin-screw extruder for melt extrusion, slicing, pulverizing, grinding, and sieving to obtain surface layer powder, where the temperature setting of each zone of the twin-screw extruder has the temperature of the first zone is 145℃, the temperature of the second zone is 145℃, the temperature of the third zone is 150℃, the temperature of the fourth zone is 155℃, the temperature of the fifth zone is 150℃, and the temperature of the machine head is 145℃ and the main engine speed of the twin-screw extruder is 150 revolutions/minute.