Corrosion-resisting properties of graphene-reinforced epoxy coating

BACKGROUND: The development of anti-corrosion coatings for marine applications is still important due to corrosion caused by salt water and weather factors. Conventional epoxy coatings have good adhesion and chemical resistance, but their protective properties can be improved by nano-based modification. Due to its unique structure and barrier properties, graphene is a promising additive to increase the corrosion resistance and mechanical strength of polymer coatings. AIM: This study aims to investigate the influence of graphene powder on the structure, corrosion resistance properties, and adhesive strength of epoxy coatings. It is focused on optimization of graphene concentration to achieve the best possible protective effect. METHODS: Graphene powder was produced by liquid-phase exfoliation of graphite followed by its sublimation dehydration allowing to preserve its structure. Epoxy coatings were modified with 0.0125, 0.025 and 0.05 wt% of graphene. To determine the protective properties, the coatings were tested in a salt spray chamber; the coating structure was analyzed using microscopic methods. RESULTS: Experiments showed that the introduced graphene reduces the number of surface micropores and improves the coating structure. The highest corrosion resistance was achieved with graphene concentration of 0.025 wt%, which is associated with its uniform dispersion in the polymer matrix and effective interaction with the epoxy binder. CONCLUSION: The study showed that adding graphene to epoxy coatings significantly improves their corrosion-resisting properties and adhesive strength. The optimum concentration of graphene (0.025 wt%) allows to create promising materials for marine shipbuilding and other applications requiring increased corrosion protection.