Improved Anticorrosion Properties of Polyurethane Nanocomposites by Ti₃C₂T_x MXene/Functionalized Carbon Nanotubes for Corrosion Protection Coatings

The corrosion protection of MXene-based composite coatings is challenging due to the relatively low dispersion of MXene in organic coatings. In this work, waterborne polyurethane (WPU) composites containing hybrid nanoadditives of Ti₃C₂T_x MXene and functionalized carbon nanotubes (CNTs) were fabricated. The thermal stability, surface hydrophobicity, surface roughness, and mechanical properties of the nanocomposites containing MXene or MXene/CNT hybrid additives were studied. Electrochemical methods, including electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization scans, were utilized to evaluate the anticorrosion properties of the nanocomposite coatings when applied to copper substrates. The polyurethane sample with 0.95 wt % Ti₃C₂T_x MXene and 0.05 wt % CNTs showed the lowest corrosion rate of 2.1 × 10^–3 μm year^–1. Additionally, the EIS results revealed that the corrosion resistance of WPU/MXene coatings significantly increased by adding 0.05 wt % CNTs. The mechanism of the improved anticorrosion performance of the WPU/MXene/CNT composite coating is illustrated. Moreover, the importance of optimizing the concentration of the CNTs is discussed to obtain better corrosion protection. The polyurethane nanocomposite coatings reported in this work present great potential as corrosion protection coatings for metals and other surfaces.