Preparation of epoxypropyl functionalized graphene oxide and its anticorrosion properties complexed with epoxy resin

Abstract

Functionalized graphene oxide (GO)/epoxy resin (EP) composite coating has attracted attention due to its advantages of epoxy resin in acid resistance, anticorrosion and having the characteristics of GO such as good chemical stability and strong electrolyte barrier properties. In this study, epoxypropyl functionalized graphene oxide (EFGO) was synthesized with a new strategy by grafting epichlorohydrin (ECH) onto the surface of GO. EFGO was then cross-linked with EP by diethylenetriamine (DETA) to fabricate EFGO/EP anticorrosive coating. The structure and property of EFGO and EFGO/EP were characterized and evaluated by various methods such as FTIR, Raman, XPS, SEM, and EIS. The results showed that the graft amount of epoxypropyl on GO surface could be effectively increased by using KI-KF catalysis system. The increase of the graft amount further improved the compatibility between EFGO and EP. EFGO/EP had a network structure with EFGO as the “central node”. The “central node” locked the movement of EP chain segment, as improving the thermal stability of EFGO/EP. The EFGO/EP coating fabricated by the EFGO, which grafted larger epoxypropyl, had good anticorrosion performance and adhesion with steel plates, showing a good barrier effect on electrolyte migration. The coating resistance reached up 4.88×108 Ω cm2.