Improvement of anti-corrosion of epoxy coating by synergistic modification of basalt scale with phytic acid

Purpose This paper aims to enhance the anticorrosion property of epoxy resin through basalt scale (B) and phytic acid (PA). Design/methodology/approach In this work, basalt scale is first modified with sodium hydroxide solution to improve its surface activity and hydroxyl content. Subsequently, phytic acid-modified basalt scale (PA-EB) is prepared by grafting PA onto the surface of etched basalt scale (EB). PA-EB is added to epoxy resin to prepare epoxy coating, and the anticorrosive properties of epoxy coating are studied. The structure and function of the materials were studied through spectrum and energy spectrum, SEM and EIS measurement. Findings PA-EB can improve the corrosion resistance of the coating. At the same time, the modified PA-EB epoxy coating (PA-EB/EP) shows better corrosion resistance. The dry adhesion of the PA-EB/EP reaches 14.95 MPa. After 1500 h of immersion in 3.5 Wt.% NaCl solution, the coating impedance remains at 9.12 MPa. Originality/value The authors have endowed the modified coating self-healing properties through the corrosion inhibition of PA, thereby further improved the corrosion resistance of the coating.