An Amino Acid Grafted Graphene Oxide as Promising Material in Poly(urea-formaldehyde)-Epoxy Microcapsules for Enhancing the Interfacial Adhesion of Epoxy Coatings

Abstract

Novel microencapsulated materials with superior anti-corrosion properties and improved adhesive strength on the metal substrate were produced by emulsion polymerization and characterized successfully. Initially, serine grafted graphene oxide was prepared and characterized through various sophisticated techniques. Then, MC-GO/epoxy and MC-GO-Ser were individually impregnated into th epoxy system and applied on the mild steel substrates. Corrosion tests were performed to evaluate the non-corrosive nature of MC-GO/epoxy and MC-GO-Ser/epoxy samples. After 7 days of exposure in saline media, MC-GO-Ser microcapsules demonstrated 80.6 % protective efficiency. Furthermore, the peel strength of 2.90 N revealed that the coating loaded with MC-GO-Ser microcapsules had improved adherence to the mild steel surface. Results of urea-formaldehyde GO-Ser microcapsules showed better corrosion protection and greater adhesive strength, which is probably because of the exceptional barrier action of microcapsules against the incursion of corrosion solution onto the mild steel surface.