Aqueous zinc plating sealing agent and preparation method thereof

The invention provides an aqueous zinc plating sealing agent and a preparation method thereof, and relates to the technical field of zinc plating surface treatment, wherein the aqueous zinc plating sealing agent comprises the following raw materials by weight: 30-40 parts of sodium silicate, 6-10 parts of methyl polyacrylate, 3-7 parts of a defoamer, 1-5 parts of a coupling agent, 3-5 parts of a phosphite-based antioxidant, 10-14 parts of sodium nitrite, 3-9 parts of fatty alcohol polyoxyethylene ether, 4-6 parts of a film forming agent, 1-3 parts of a stabilizer, and 100 parts of water. The preparation method comprises: (1) weighing the raw materials; (2) preparing a solution a; (3) preparing a solution b; (4) preparing a solution c; (5) preparing a solution d; and (6) mixing the solutiona and the solution d. According to the present invention, the anticorrosive coating prepared by using the aqueous zinc plating sealing agent has advantages of smoothness, uniformity, no color change,strong corrosion and stro