Enhancing corrosion resistance and self-healing of water-borne epoxy coatings using TiCTx-supported tannic acid on UIO-66-NH.

In this study, we developed a composite material comprising UIO-66-NH encapsulated tannic acid (TA) loaded on TiCTx to improve the corrosion resistance of water borne epoxy (WEP) coatings. The successful synthesis of the material was determined by FT-IR, XRD, XPS, EDS, TGA, SEM and TEM characterization. Furthermore, ultraviolet (UV)tests were conducted to evaluate the release rate of TA at varying pH levels, revealing a release rate of approximately 95 % at pH 2. Electrochemical impedance spectroscopy (EIS) results over 60 d indicated that the R value of TU-T/WEP remained unchanged at 3.934 × 10, demonstrating a two-order magnitude increase compared to those of pure epoxy coatings, attributed to the synergistic active and passive protection of TU-T materials. The self-healing ability of the TU-T/WEP coating was validated through manual scratch experiments. Additionally, the EIS test showed that the R value of TU-T/WEP coating increased to 3.5 × 10 after 72 h, representing a two-order magnitude increase over that of the WEP coating alone. This study introduces a novel approach using green tannic acid as a corrosion inhibitor and amino-functionalized TiCTx with UIO-66-NH to enhance corrosion resistance and self-healing aproperties of coatings.