Enhancing the protective performance of waterborne polyurethane coatings by non-covalent functionalized MXene

To address the issue of weak protective performance of green water-based polyurethane (WPU) arising from intrinsic defects and poor interfacial compatibility with MXene (Ti 3 C 2 T x ), we report a one-step, noncovalent functionalization of MXene using low-toxicity corrosion inhibitors—tannic acid and cerium ammonium nitrate. Incorporation of the modified MXene markedly enhances barrier and interfacial properties through synergistic mechanisms. After 25 days of immersion, coatings containing the tailored filler exhibit a 19-fold increase in low-frequency impedance modulus (|Z | 0.01Hz ), 20.49% lower saturation water uptake, a 27.03% higher water contact angle, and a 27.43% increase in dry adhesion strength. Notably, the films display corrosion-inhibiting self-healing upon mechanical damage, effectively mitigating substrate degradation. This eco-friendly filler modification offers a practical route to overcome the protection limitations of WPU and may accelerate the development of environmentally friendly anticorrosion coatings.