Effect of high-temperature mechanochemistry method modified TiO₂ on the dispersibility and corrosion resistance of TiO₂-epoxy coatings

Abstract

Purpose

The purpose of this paper is to enhance the compatibility of titanium dioxide in epoxy resins and thus the corrosion resistance of the coatings.

Design/methodology/approach

In this work, TiO₂ was modified by the mechanochemistry method where mechanical energy was combined with thermal energy to complete the modification. The stability of modified TiO₂ in epoxy was analyzed by sedimentation experiment. The modified TiO₂-epoxy coating was prepared, and the corrosion resistance of the coating was analyzed by open circuit potential, electrochemical impedance spectroscopy and neutral salt spray test.

Findings

High-temperature mechanical modification can improve the compatibility of TiO₂ in epoxy resin. At the same time, the modified TiO₂-epoxy coating showed better corrosion resistance. Compared to the unmodified TiO₂-epoxy coating, the coating improved the dry adhesion force by 61.7% and the adhesion drop by 33.3%. After 2,300 h of immersion in 3.5 Wt.% NaCl solution, the coating resistance of the modified TiO₂ coating was enhanced by nearly two orders of magnitude compared to the unmodified coating.

Originality/value

The authors have grafted epoxy molecules onto TiO₂ surfaces using a high-temperature mechanical force modification method. The compatibility of TiO₂ with epoxy resin is enhanced, resulting in improved adhesion of the coating to the substrate and corrosion resistance of the coating.

Citation

Liu, Y., Zhang, Q., Wang, J., Shao, Y., Xu, Z., Wang, Y. and Wang, J. (2023), "Effect of high-temperature mechanochemistry method modified TiO₂ on the dispersibility and corrosion resistance of TiO₂-epoxy coatings", Anti-Corrosion Methods and Materials, Vol. 70 No. 6, pp. 449-458. https://doi.org/10.1108/ACMM-05-2023-2809