Improvement in inhibition performance of anti-corrosion coatings using polyolefin matrix embedded with modified TiO2 nanoparticles

Abstract

Corrosion remains a critical issue for steel structures, leading to costly repairs and potential failures in industrial sectors. This study presents the development and characterization of polyolefin coatings for enhanced corrosion protection. Initially, the porous TiO2 nanoparticles were synthesized using the sol-gel method, followed by their modification through the encapsulation of sodium benzoate (SB) as a corrosion inhibitor. Modified Polyolefin coatings were prepared by incorporating modified nanoparticles (TiO2 loaded with sodium benzoate) into the polyolefin matrix, and an unmodified/blank polyolefin coating was prepared without any additive in the polyolefin matrix. The loading of the inhibitor into porous TiO2 was 10 % analyzed using thermogravimetric analysis. Furthermore, the electrochemical analysis revealed significant improvements in the corrosion resistance and barrier properties of the modified coatings compared to the unmodified blank coatings. Specifically, after 7 days in a corrosive environment, the blank coating pore resistance dropped from 1 × 1010 Ω·cm2 to 5 × 108 Ω·cm2, while the modified coating maintained a high pore resistance of 5 × 1011 Ω·cm2. A localized corrosion study for scratched blank polyolefin coatings showed growing corrosion activity from 5 h of immersion, while modified coatings ceased the detectable activity before 4 h of immersion, which evidenced the improved corrosion inhibition efficiency of the modified coating. This stability in corrosive environments was attributed to the successful loading of modified nanoparticles (TiO2/SB), where SB served as an active agent by forming a protective film on the steel substrate. Which inhibits the corrosion processes along with Ti-based compounds and prevents corrosion propagation under the damaged coating. The enhanced hydrophobic nature of 99° and electrochemical properties support the suitability of these coatings for corrosion protection of steel in various industries.