Study on anticorrosion properties of reduced graphene oxide reinforced waterborne epoxy coating

Background: The traditional epoxy zinc-rich coating releases some harmful substances such as VOC during the service process, which pollutes the environment and causes great harm to people. Waterborne epoxy coating is an environmentally friendly, non-polluting potential coating. Objective: In this paper, a new reduced graphene oxide (RGO) reinforced waterborne epoxy coating is developed. Methods: Reduced graphene oxide (RGO) is obtained by modifying graphene oxide (GO). The addition of RGO to waterborne epoxy coatings is designed to improve the corrosion resistance of the coatings. The anticorrosion properties of the coating are investigated by electrochemical methods. Results: After the coating was immersed in 3.5wt% NaCl solution for 15 days, the corrosion current of the coating without RGO is greater than that of the coating containing RGO. Coatings with RGO have higher impedance modulus than coatings without RGO. Coating with 0.3% RGO has better corrosion resistance. After the coating was immersed in the salt solution for 55 days, the impedance modulus of the coating with 0.3% RGO increased by 349.11% compared to the coating without RGO. The coating with 0.3% RGO has the minimum corrosion current density, and the maximum polarization resistance and corrosion voltage. Conclusion: The waterborne epoxy coating with 0.3% RGO has the best anticorrosion.