The Effect of a Chemically Modified Graphene in Water Based Corrosion Coating

Research in the development of new corrosion coatings is of major economic importance. Recently, nanocomposite based corrosion coatings containing nanostructures limiting diffusion of aggressive corrosion species, have been reported. Graphene is a one atom thickness sheet, formed by a hexagonal arrangement of carbon atoms with excellent thermal, electric and mechanical properties. This work investigates the use of chemically modified graphene (CMG) as an additive in commercial vinylic corrosion coatings. It is expected as the diffusion of aggressive species diminishes through the coating from the presence of graphene, therefore the coating corrosion protection behaviour improves and so the metal damage reduces. The CMG was prepared by graphite oxide thermal self reduction. Afterwards a coating was formulated based on a vinyl acrylic paint and 1, 3, 5 and 10% wt CMG mixture. Ferric nitrate was added as an inhibitor. The coating was then applied to 1045 carbon steel sheet and dried at room temperature. Electrochemical evaluation was performed in 3% NaCl solution and coatings were evaluated electrochemically and characterized using electron scanning microscopy (SEM) to observe their morphology.