The influence of the chemically bonded interface between fillers and binder on the failure behaviour of an epoxy coating under marine alternating hydrostatic pressure

• Chemically bonded interface of fillers/binder improves the dispersion of fillers.
• Chemically bonded interface of fillers/binder reduces the initial defects of the coating.
• Chemical bonding increases the compactness and mechanical properties of the coating.
• Chemically bonded interface retards the water diffusion through the coating under AHP.

The failure behaviour of epoxy resin-based modified mica (MM) coating has been investigated under marine alternating hydrostatic pressure (AHP). The results indicate that the chemically bonded interface forms between MM fillers and epoxy binder, which significantly enhances the compactness and the mechanical properties of coating by promoting the dispersion of fillers and reducing the defects of coating. The improvement of the fillers/binder interface weakens the permeation of water and the deterioration of coating structure which are caused by the drawing force of AHP. Hence, the performance of epoxy coating is promoted under AHP environment.