A Smart Anticorrosive Epoxy Coating Based on Environmental-Stimuli-Responsive Copolymer Assemblies for Controlled Release of Corrosion Inhibitors

Inspired by the various applications of self-assembled amphiphilic polymers in aqueous solution, a novel semi-amphiphilic copolymer is designed, which can self-assemble in organic systems by taking advantage of the compatibility difference between epoxy and the units with different structures in the polymer chains. A novel kind of polymer, poly(syringaldehyde methacrylate)-co-poly(dopamine methacrylate) is prepared by reversible addition-fragmentation chain transfer polymerization, which contains aldehyde groups and is further used to prepare the polymer/guanine conjugate by forming the Schiff base. The polymer/guanine conjugate is semi-amphiphilic, since the compatibility between dopamine methacrylate unit and epoxy is better than that between syringaldehyde methacrylate and epoxy, and therefore assemblies are formed in the organic system when it is added into the epoxy resin to prepare the anti-corrosive coating. The imine linkage is responsible for the pH-controlled release of the corrosion inhibiters, namely guanine, from the core of the assemblies. The self-assembled behaviors of the semi-amphiphilic copolymer in epoxy are investigated by dynamic light scattering and scanning electron microscopy. The stable encapsule and controlled-release of the inhibitors are confirmed by UV spectrophotometry. The properties of the smart coatings are comprehensively studied.

Automated summary

Inspired by the applications of self-assembled amphiphilic polymers, a novel semi-amphiphilic copolymer with excellent compatibility in organic systems is designed for anti-corrosive coating. The semi-amphiphilic copolymer can self-assemble and release inhibitors through pH-controlled imine linkage.