Developing a Green PDA@Ce-MOF@TA-Fe Composite to Provide pH-Responsive and Self-Healing Anti-Corrosion Performance for Waterborne Epoxy Coatings

Waterborne epoxy coatings are favored for their environmental friendliness and low volatile organic compounds (VOC) emissions. However, traditional waterborne epoxy coatings have limitations in terms of barrier properties and self-healing ability, resulting in poor long-term corrosion protection. To overcome this shortcoming, a novel green composite based on PDA@Ce-MOF@TA-Fe (PCTF) was developed in this study, aiming to construct a high-performance coating system with enhanced corrosion protection, pH responsiveness, and self-healing properties. The EIS measurements demonstrated a significant enhancement in the barrier property and self-healing capability of the waterborne epoxy coating incorporated with the PCTF composite (PCTF/WEC). After 40 days of immersion in corrosive conditions, the impedance of the PCTF/WEC coating remains at 9.82 × 10 8 Ω·cm 2 , which is much higher than that of the WEC coating alone (1.47 × 10 6 Ω·cm 2 ). PCTF/WEC coating also shows excellent pH response in acidic environments (pH = 3). Salt spray tests and UV irradiation tests confirm the coating's good weathering resistance. This study provides a promising strategy for the development of long-lasting and environmentally friendly anti-corrosion coatings.