Recyclable and Thermally Responsive Self-healing Waterborne Polyurethane Based on Diels-alder Reaction

Abstract A type of waterborne polyurethane with excellent self-healing and recyclable properties was successfully prepared by introducing Diels-Alder (DA) reaction groups into the polymer matrix. The results showed that all obtained waterborne polyurethane dispersions with a particle size of about 400 nm, had good dispersibility and storage stability, which was confirmed by the zeta potential and the particle size test. FT-IR was used to verify the thermal reversibility of DA and the retro-DA reaction on the WPU-DA films. In addition, the thermal stability of the WPU-DA films was significantly improved due to the introduction of the DA bond. The cross-linked waterborne polyurethane had good reprocessability and had great potential application prospects in intelligent materials.