Synergistic effect of 8-HQ@CeO2 for enhanced corrosion resistance of self-healing polyurethane coating for corrosion protection of mild steel

作者：Yinjie Xu, Ruiqi Liu, Zengfu Shao, Chen Liang, Wangru Wei, Shihua Dong, Haibo Wang · 发表于：Progress in Organic Coatings · 年份：2023 · DOI：10.1016/j.porgcoat.2023.108015 · 被引用次数：30 · 研究领域：Corrosion Behavior and Inhibition、Polymer composites and self-healing、Surface Modification and Superhydrophobicity

The anticorrosive qualities of organic coatings can be enhanced by the inclusion of corrosion inhibitors , which is helpful for ensuring the long-term anticorrosive performance of the coatings. Taking advantage of the fact that polydopamine contains multiple functional groups, the 8-HQ@CeO 2 polyurethane composite coating was prepared by coating it on the surface of CeO 2 and adsorbed with 8-Hydroxyquinoline (8-HQ), and its anticorrosion performance in 3.5 wt% NaCl solution was investigated. After 120 days of immersion, the polyurethane composite coating containing both CeO 2 and 8-HQ organic/inorganic dual corrosion inhibitors exhibited excellent long-term corrosion resistance . Its impedance modulus at 0.01 Hz (10 8 Ω·cm 2 ) was two orders of magnitude higher than that of the polyurethane composite coating containing only CeO 2 (10 6 Ω·cm 2 ). The coating also incorporated dynamic Diels-Alder (DA) bonds to create its self-healing characteristics. The produced composite coatings could exhibit effective self-healing behavior under sunlight thanks to the superior photothermal characteristics of polydopamine (PDA), and their mechanical and anticorrosive properties were substantially unaltered before and after self-healing. The strategy utilizes the synergistic anticorrosive effect of CeO 2 and 8-HQ and dynamic DA bonding to achieve the long-term anticorrosive performance of the coating and proposes a new method to protect metal substrates.