Transparent, Tough, and Self-Healable Elastomer Based on Dynamic Dual Cross-Linking of Coordination and Disulfide Bonds

Abstract

Tough and stretchable self-healing elastomers are highly desired for applications in wearable devices, soft robotics, and human motion detection. However, most elastomers that heal at room temperature suffer from poor mechanical properties. In this study, inspired by mussels, a dual cross-linked strategy that combines weak disulfide bonds and strong coordination bonds is proposed to solve the above-mentioned problems. The obtained transparent silicone elastomer shows high tensile stress (1.4 MPa), stretchability (2006%), toughness (14.7 MJ m–3), and excellent healing efficiency (97%) at room temperature. The outstanding performance of the silicone elastomer is attributed to the synergistic effects of coordination and disulfide bonds. In the dual cross-linked network, disulfide bonds are introduced as sacrificial bonds to endow the elastomer with excellent stretchability and self-healing property, and coordination bonds are conductive to improving robustness and elasticity. Given the good mechanical and healing property of the developed silicone elastomer, it enables the easy construction of flexible strain sensors with excellent electrical conductivity and sensing stability. Our study provides insights into the development of self-healable silicone elastomers for flexible electronics.