A surface coating agent for automotive exhaust pipe sealing gaskets and its preparation method

Abstract

This invention relates to the field of automotive exhaust pipe coating preparation technology, specifically disclosing a surface coating agent for automotive exhaust pipe gaskets and its preparation method. The preparation method involves adding acetone, polyvinyl alcohol, and benzophenone tetracarboxylic dianhydride to a reaction vessel in a specific ratio for esterification to obtain an ester solution. Alkali solution and epoxy resin are then added to the ester solution and reacted for 2-4 hours to obtain a water-based epoxy emulsifier. The water-based epoxy emulsifier and epoxy resin are then reacted under preset conditions to obtain a water-based epoxy resin emulsion. The water-based epoxy resin emulsion, filler, dispersant, and thickener are then added to the reaction vessel and mixed thoroughly. A stabilizer and defoamer are added and mixed again to obtain the surface coating agent for automotive exhaust pipe gaskets. Compared with existing technologies, the surface coating agent obtained by this invention, together with the curing agent, improves coating adhesion while preventing the formation of pores and pinholes in the obtained coating structure, enhancing the coating's corrosion resistance and density, thereby improving the gasket's acid and water resistance.

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