Self-healing polyurethane elastomer based on 2-ureido-4[1H]-pyrimidinone

Unlike the organisms in nature, the synthetic materials are difficult to repair the damage via self-regulation. Even the self-healing materials generally require the external stimuli (e.g., temperature, pressure, light, etc) to repair themselves. In this paper, self-healing polyurethane elastomer was designed and prepared based on 2-ureido-4[1H]-pyrimidinone compound by the simple physical blending method. The tensile strength and the elongation at break of the self-healing polyurethane elastomer were 0.65 MPa and 623.1%, respectively. The healing performance was measured by cut-off experiment, showing that the fracture of the self-healing polyurethane elastomer was healed at room temperature without external stimuli and kept excellent mechanic properties. The healing efficiencies of the tensile strength and the elongation at break were achieved to 87.7% (0.57 MPa) and 71.7% (446.7%) after healing at room temperature with 30 h, respectively. When the temperature was up to 80 °C, the healing time curtailed at 1 h. And the tensile strength and the elongation at break were recovered to 0.59 MPa and 532.1%, respectively. These promising results provide a strategy that allows increasing the life cycle of materials, adapting them to a circular economy model, thus reducing the generation of waste.