Corrosion resistance of epoxy coating on mild steel through polyamidoamine dendrimer-covalently functionalized graphene oxide nanosheets

[Display omitted] •Epoxy coating was reinforced with polyamidoamine dendrimer-reduced graphene oxide (GO-PAMAM) nanosheets.•Successful covalent functionalization and reduction of GO by PAMAM was confirmed.•GO-PAMAM nanosheets significantly enhanced the coating protection performance of epoxy coating. Epoxy coating was reinforced with polyamidoamine dendrimer-reduced graphene oxide nanosheets (GO-PAMAM) to obtain a high-performance anti-corrosion system. The GO-PAMAM was characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and UV–vis analysis. Results confirmed that PAMAM molecules successfully grafted on the GO surface, resulting in the lamellae d-spacing increment. Results of electrochemical impedance spectroscopy (EIS) and salt spray test evidenced that in the presence of 0.2 wt.% GO-PAMAM the epoxy coating corrosion protection properties were effectively enhanced. It was found from the results that the PAMAM could enhance the GO particle dispersion in the epoxy through increasing the GO nanosheets interlayer space and surface hydrophilic nature reduction.