Multiple Hydrogen Bonds Enhance the Mechanical Strength, Conductivity, and Self-Healing Properties of Conductive Elastomers

Conductive elastomers have attracted considerable attention because they can mimic the tactile sensation of human skin while possessing mechanical properties comparable to those of skin. When used as skin sensors, these materials inevitably suffer damage, highlighting the importance of their self-healing capabilities. Moreover, the energy dissipation mechanism of conductive elastomers under stress remains unclear. To address this issue, we developed a conductive elastomer based on polymerizable low-melting-point solvents combined with tannic acid (TA) to reinforce the hydrogen-bonded framework. This design endows the aqueous conductive elastomer with both excellent self-healing performance and enhanced mechanical properties, as demonstrated by its fracture stress of 1.5 MPa, fracture strain of 815%, and capability to recover over 76.7% of its original mechanical strength after 24 h of room-temperature self-healing. As a strain sensor, it exhibits high sensitivity (GF ≈ 11.51), rapid response time, and outstanding sensing stability. Boasting these excellent properties, the conductive elastomer is promising for sustainable electronic skin applications. Molecular dynamics simulations and finite-element analysis confirm that the 30 wt % TA-derived dynamic hydrogen-bond network facilitates surface segment interdiffusion, energy dissipation, and stress concentration suppression, improves ductility, and breaks the traditional performance trade-offs.