Effect of addition of non-functionalized graphene oxide in a commercial epoxy resin used as coating

The paper studies the effect of incorporating graphene oxide (GO) without surface functionalization on a commercial epoxy resin. GO was dispersed in a commercial epoxy resin at concentrations of 0 wt.%, 0.1 wt.%, 0.5 wt.%, 1 wt.%, and 3 wt.%. The resultant materials were deposited on carbon steel substrates, followed by the use of a 5 wt.% aqueous NaCl electrolyte, to evaluate the effectiveness of their anticorrosive coating function. Scanning electron microscopy (SEM) analysis showed that the GO was homogenously dispersed in the polymer matrix, resulting in flat and smooth surfaces. The X-ray diffraction (XRD) results showed that although GO was highly dispersed in the polymer matrix, multilayer graphene was also obtained after curing. The anticorrosive properties were evaluated by electrochemical impedance spectroscopy (EIS) at various exposure periods. Analysis of the prepared samples indicated that the best anticorrosion performance among them was available with the 0.5 wt.% GO coating. The obtained results indicate that GO–polymer matrix composites provide improved corrosion protection properties even after 500 h exposure to the NaCl solution.