Thermoplastic polyurethanes (TPUs) are renowned for their superior mechanical properties, including elasticity, durability, and abrasion resistance, which make them indispensable in industries such as automotive, construction, and electronics. However, conventional TPUs often lack self-healing capabilities, limiting their lifespan and increasing maintenance costs. This study addresses this limitation by developing a novel TPU elastomer (PUAN-1) that incorporates gold nanoparticles (AuNPs) and disulfide bonds to enhance both mechanical strength and self-healing efficiency. The AuNPs serve as a reinforcing phase, improving the TPU's mechanical performance by strengthening the hard segments and promoting dynamic disulfide bond reformation through photothermal effects. This innovative approach enables the TPU to achieve rapid self-healing under mild conditions while maintaining excellent mechanical properties. Experimental evaluations demonstrated that PUAN-1 exhibited an ultimate tensile strength of 4.4 MPa, an elongation at break of 1165%, and a toughness of 39.7 MJ/m, significantly outperforming conventional TPUs. Additionally, PUAN-1 displayed a high self-healing efficiency, with over 88% recovery in mechanical properties within two hours of damage. Conversely, a higher concentration of AuNPs, as in PUAN-2, was found to hinder both self-healing and mechanical performance due to restricted chain mobility and suppressed microphase separation. These findings highlight the critical balance required in optimizing AuNP content to maximize both reinforcement and flexibility. The developed TPU elastomer presents a promising candidate for applications demanding durable, self-repairing materials, such as wearable electronics, flexible sensors, and biomedical devices. This study provides valuable insights into the design of advanced TPUs that combine high mechanical robustness with effective self-healing capabilities, offering significant potential for use in dynamic and demanding environments.
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