Effect of phytic acid modified epoxy resin on rusty-tolerant coating

During steel processing, surface treatment often fails to meet the Sa2.5 standard or higher, sometimes requiring manual rust removal. Even after manual cleaning, rust products frequently remain on the steel surface, severely compromising the performance of traditional anti-corrosion coatings. In this study, we grafted phytic acid onto the molecular chain of epoxy resin through chemical synthesis to produce a composite resin with rust conversion capability and determined optimal synthesis parameters. The water absorption rate and electrochemical impedance spectroscopy data indicate that although the addition of modified resin increases a coating's hydrophilicity, the resin enhances the degree of cross-linking and reacts with the rust layer, forming a new shielding layer and improving the coating’s overall corrosion resistance. The coating with a 20% modified resin exhibited the best corrosion resistance.