Preparation and Properties of Polyurethane with Self-Healing Function by Solvent-Free Method

Self-healing polyurethane materials with excellent mechanical properties have a wide range of applications, including textiles, clothing, leather, and flexible electronics. However, determining methods to obtain this material in green and environment-friendly ways is an interesting and challenging task. In this study, a series of self-healing polyurethane materials with soft segments containing diselenide bonds and hard segments including multiple hydrogen bonds were prepared using a solvent-free method. The characterization results demonstrated that the T–Se–SFPU–2 sample exhibited both favorable self-healing function as well as mechanical properties with a tensile breaking strength of 6.15 MPa, and the greatest healing effect was achieved after 6 h at room temperature under visible light. The research results further demonstrated that the hydrogen bond in the hard segment can considerably improve the mechanical properties of polyurethane. The best micro-phase separation was achieved by controlling the hydrogen bond content in the hard segment, achieving a force balance between the soft and hard segments, and finally, the optimal balance between the self-healing performance and mechanical strength of polyurethane was achieved. These results provide a new strategy for preparing polymers with different self-healing capabilities.