Preparation of self-healing superhydrophobic polyacrylate coatings based on silica matrix-microcapsules containing corrosion inhibitor for long-term corrosion protection

Abstract

In this study, a superhydrophobic coating with self-healing properties for carbon steel corrosion protection was developed, incorporating fluorinated silica microcapsules containing corrosion inhibitor and fluorinated siloxane acrylate copolymer (FSC). Triethanolamine (TEA), functioning as a corrosion inhibitor, was encapsulated in silica matrix-microcapsules through a water-in-oil (W/O) interfacial condensation method. Furthermore, the prepared silica microcapsules underwent 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) fluorination modification under the catalytic action of ammonia. Upon mechanical disruption of the superhydrophobic coating, the microcapsules liberate rust inhibitors, thereby instigating the formation of a fresh passivation layer on the surface of mild steel, perpetuating its defense against corrosion. These prepared superhydrophobic coatings manifest commendable antifouling, self-cleaning, and durability attributes, collectively representing pivotal traits requisite for efficacious metal surface anticorrosion. Electrochemical impedance spectroscopy (EIS) assessments conclusively substantiate the pronounced enhancement in the corrosion resistance of mild steel surfaces upon application of the synthesized superhydrophobic coating. More importantly, the self-healing capability of the superhydrophobic rust-resistant coating has been confirmed through EIS testing. Specifically, following mechanical damage to the superhydrophobic coating, the corrosion resistance of specimens housing rust inhibitors markedly exceeds that of counterparts devoid of these inhibitors. The innovative amalgamation of intelligent composite superhydrophobic coatings, underscored by these findings, underscores its broad applicability in combating metal corrosion, thereby holding substantial promise in this domain.