Manufacturing of a Smart Coating by Using SiO₂ Nanoparticles and Hexamine

Recent years have seen a significant increase in interest in smart anticorrosion coatings, which can detect corrosive situations and autonomously discharge corrosion inhibitors. The mild steel surface was coated with pH-sensitive nanocontainers that had been manufactured and doped into an epoxy coating. Elemental mapping, thermogravimetric analysis/differential scanning calorimetry, and electrochemical impedance spectroscopy (EIS) methods were used to examine dispersion homogeneity, thermal durability, and corrosion tolerance. The findings indicated that nanocontainers dispersed uniformly in epoxy and that doping nanocontainers had no effect on the epoxy properties. When immersed in NaCl solution with nanocontainer doping concentrations of 3%, 6%, and 9%, EIS findings showed a rise in epoxy corrosion resistance following 5 d, 10 d, 15 d, 25 d, and 30 d. This enhancement was attributable to the smart release of corrosion inhibitors to protect steel surfaces. Infrared thermography and corroded substrate images confirmed the EIS data. The Korsmeyer-Peppas kinetic model was the best model for fitting the obtained data.