Dual-Dynamic Polyurethane Elastomers Integrating High Strength and Room-Temperature Self-Healing for an E-Skin

Conventional flexible sensors often face a compromise between mechanical properties and self-healing ability, which severely limits their long-term usability and functional reliability. In this work, we report a series of polyurethane elastomers synergistically reinforced by multiple hydrogen bonds and disulfide bonds, which integrates high mechanical strength and autonomous self-healing ability. The optimized composition, PU-BHO0.3-BHDS0.7, achieved an excellent breaking strength of ∼39.73 MPa, an elongation at break of ∼1568.61%, and a fracture energy of ∼157.75 kJ·m–2. It also exhibited an ultrahigh self-healing efficiency of ∼99.29% at room-temperature, retaining ∼85.90% even at −18 °C. Based on this elastomer, we fabricated a multilayer resistive sensor using liquid gallium (LG) and carbon black (CB) as conductive electrodes. The healed sensor maintained a gauge factor and resistance response nearly identical to its original state, demonstrating complete functional restoration. This work provides a feasible strategy for developing high-performance self-healing materials suitable for durable flexible electronic devices, such as human motion sensors.