Advancing steel protection with Ceria@Talc-8-hydroxyquinoline modified Polyurethane coatings

Abstract

This research delves into a hybrid framework involving the synthesis of composite particles combining ceria-modified talc (CeO2@Talc) through a chemical precipitation method. The hybrid particles were then loaded with 8-Hydroxyquinoline (8-HQ) to serve as a corrosion inhibitor. The resulting CeO2@Talc-8HQ hybrid particles were subsequently incorporated into a polyurethane (PU) matrix and deposited on steel substrate to investigate and assess their barrier properties. The synthesized particles and developed coatings were characterized in detail utilizing various techniques. The Brunauer–Emmett–Teller (BET) results showed a decrease in the specific surface area and pore volume of modified particles as compared to that of pristine talc. These results demonstrated the successful loading and modification of the particles. The thermal gravimetric analysis (TGA) results showed excellent thermal behavior with only 2 % weight loss beyond 900 °C of the modified CeO2@Talc particles. The potentiodynamic polarization results represented 76.28 % increase in the corrosion inhibition efficiency in the presence of the modified particles. When these modified hybrid particles were reinforced (1.wt%) into the PU matrix, they exhibited an impressive impedance modulus of 56.14 GΩ.cm2 at 0.01 Hz, outperforming blank PU coatings which showed 0.002 GΩ.cm2 after four weeks of immersion in a 3.5 wt% saline solution. The incorporation of modified particles into the PU matrix results in significant improvements in various observed parameters such as the lowest break point frequency, damage index, and intersection frequency of the bode plot. These positive outcomes indicated that the modified coatings efficiently blocked the micropores of the PU matrix, preventing the diffusion of electrolytes into the coatings. Overall, this study not only introduced a novel structural design for superior corrosion mitigation but also demonstrated promising potential of corrosion protection for industrial applications.