Acid‐Responsive Anticorrosion Microcapsules for Self‐Protecting Coatings

Encapsulated anticorrosion agents provide a suitable alternative to dispersion of metal-based compounds in protective polymeric coatings on metal substrates. Stimuli-responsive microcapsules enhance protection abilities by autonomously responding corrosion-induced environmental changes, rather than relying damage-induced mechanical stimuli. This work reports pH-responsive with triggered release over wide range acidic pH values (pH < 6) and robust enough be incorporated commercial solvent-based epoxy coatings. The responsiveness is achieved integrating acid labile ketals that undergo rapid hydrolysis within the cross-linked polyamide shell readily acetylenic diol or jojoba oil as anticorrosive agent. are stable up temperature 150 °C long-term room stability 3 months. Degradation kinetics quantified at various levels (1 ≤ 9) using 1H NMR gas chromatography, respectively. Microcapsules exhibit complete under 5 min 1 ≈2 hours 5, Coating performance evaluated electrochemical corrosion tests conducted wt% salt solutions varying concentration coating. Inhibition efficiencies 70% saltwater solutions.