Durable, Super-Resilient, and Ultra-Strong Polyurethane Elastomers Via a Dense Hydrogen Bond Cross-Linking Strategy

Reinforced and toughened elastomers are widely used in the automotive industry, medical health, flexible electronics, and other fields. However, most of the reported elastomers cannot maintain or return to their initial excellent properties in time after suffering large deformation with obvious residual strain, and the performance will be greatly reduced after prolonged use. Here, we report a thermoplastic polyurethane elastomer (PU-OD) cross-linked solely by high-density hydrogen bonds, which exhibits high tensile strength (98.5 MPa), ultrahigh elastic resilience (a small residual strain of 50% after recovering at 600% elongation), ultrahigh transparency (greater than 98%), healing (healing efficiency greater than 97%), and high durability (including UV resistance, thermal oxidation resistance, and solvent resistance). The elasticity of PU-OD elastomers exhibits historical maximums among previously reported thermoplastic elastomers due to the fact that the molecular chains of PU-OD contain a smaller number of sacrificial bonds to each other relative to typical thermoplastic elastomers. Moreover, PU-OD also exhibits excellent light transmission and durability after thermal oxidation aging due to its molecular structure which does not contain aromatic groups, and it shows excellent compatibility between soft and hard segments. The design strategy of PU-OD elastomer provides an important idea for the preparation of practical and high-performance elastomers with super durability, high resilience, high strength, and ultrahigh transparency.