A novel design for water-based modified epoxy coating with anti-corrosive application properties

•The influencing factors of the polysulfide rubber emulsion are investigated.•The anti-corrosive property and mechanical behaviour of the epoxy coatings are investigated.•The relationship between anti-corrosive property and microstructure of the epoxy coatings are discussed.•Polysulfide rubber modified epoxy coating has better anti-corrosive property than that of the unmodified epoxy coating.

In this study, a polysulfide rubber emulsion was synthesized through the pre-emulsification of polysulfide rubber by mixed-emulsifiers and polyvinyl alcohol as a weight stabilizer and the emulsification by adding deionized water dropwise at a speed of 1 ml/min, stirring at a speed of 1500 rpm and adjusting pH to 8 by ammonia. The epoxy coating was modified by the polysulfide rubber emulsion. The anticorrosive coating was prepared by using waterborne amine dispersion as a curing agent and polysulfide rubber as a modifier. It had a good chemical resistance and excellent overall mechanical performance. The coatings were characterized by Tafel polarization curves and Scanning electron microscope.