Self-Lubricating and Self-Healing Polyurethane Nanocomposites Based on Aminated-Ti₃C₂T _x

Self-healing polyurethane is a matrix material that can effectively extend the service life of composite materials. The layered two-dimensional Ti3C2Tx material has weak interlayer van der Waals forces, which can undergo slip and form transfer films during friction, reducing shear strength and improving the lubrication performance of the material. Therefore, we introduced two-dimensional Ti3C2Tx into a self-healing polyurethane matrix to improve the lubrication performance of the matrix material. A dual-ion self-healing polyurethane (SPU) was prepared using N-methyl diethanolamine, hexamethylene diisocyanate, and 1,3-propane sultone as raw materials. Ti3C2Tx was prepared by chemical etching, and NH2-Ti3C2Tx was obtained by chemically grafting amino groups onto the surface of Ti3C2Tx using amino-propyltriethoxysilane. Then, it was mixed into the SPU matrix to obtain the NH2-Ti3C2Tx/SPU composite material. Compared with pure SPU, the friction coefficient and wear rate of the system were reduced by 79.7% and 97.8%, respectively. Under 75%RH and 20 degrees C conditions, self-healing could be achieved rapidly within 5 min, with a self-healing efficiency of 84.4%. The kind of self-lubricating and self-healing polyurethane modified by amination-Ti3C2Tx is expected to be applied in automotive, electronics, and biomedicine.