A photocurable ultra-tough eutectic gel with coordination crosslinking used for wearable sensors and TENG flexible electrodes

Abstract

Flexible polymer molecular chains are of great interest to researchers in the field of flexible wearable electronics due to their unrivaled flexibility and ductility. However, achieving high toughness, high elasticity, environmental stability and easy machining of flexible electronic materials remains a challenge. In this study, we present a photocurable eutectic gel mainly composed of DMAPS, AAc, Zr⁴⁺ and deep eutectic solvents (DES). Due to the strong coordination between zirconium ions and polymer networks, the gel can be endowed with excellent properties, such as excellent tensile strength (1.14 MPa), low hysteresis (5 kJ·m⁻³) and good adhesion (above 40 kPa). DES can not only give the gel good electrical conductivity, but also maintain the stability of the gel to ensure that the leakage or volatilization of the solvent will not occur in use. The properties mentioned above allow the gel to achieve a sensitivity factor of up to 1.7 over a small strain range, demonstrating its potential applications in the field of flexible strain sensors and triboelectric flexible electrode materials. What’s more, the gel can be used to prepare complex geometric shapes with high precision through digital light processing (DLP) based 3D printing technology. Therefore, this work introduces a novel approach for the development of highly stable flexible wearable devices, which has the potential to expand the applications of eutectic gels.