Anticorrosive and UV-blocking waterborne polyurethane composite coating containing novel two-dimensional Ti3C2 MXene nanosheets

In this work, Ti 3 C 2 MXene, a novel two-dimensional nanosheet, was introduced to waterborne polyurethane (WPU) coatings to prepare a composite coating. First, MAX phase materials were in situ etched by HF acid and further intercalated by water molecules to obtain exfoliated single-layer MXene nanosheet. And then, composite coatings were prepared via solution-blending low addition (0–0.4 wt%) of MXene, self-prepared waterborne polyacrylate emulsion (PAE) and isocyanate hardener, applying on Q235 mild steel. Results of AFM, XRD SEM and SEM–EDS confirm that single-layer MXene nanosheets with large lateral-to-thickness ratio are successfully prepared and achieved homogenous distribution within WPU matrix. With 0.4 wt% MXene incorporated, the WPU/Ti 3 C 2 MXene composite coatings reach a lowest corrosion current of 2.143 × 10 –6 A/cm 2 , a decrease of one order of magnitude compared with blank WPU (1.599 × 10 –5 A/cm 2 ) and own an excellent UV-blocking property (almost block the whole UV light). Graphical abstract