Baking-inspired process for fully physically crosslinked polyacrylic acid ionic gels with excellent moldability and versatility assiated by ionic liquid

Abstract

Ionic gels have gained significant traction in the realm of flexible devices due to their remarkable stretchability, non-volatility, and high ionic conductivity. However, the limited mechanical properties of these gels, intricate preparation methods involved, and the challenges in large-scale manufacturing present significant barriers to their practical implementation in flexible devices. Simulated baking technique, the present study involved the synthesis for a series of high-performance polyacrylic acid (PAA) based ionic gels through one-pot heat-induced polymerization in a mixture comprising 1-ethyl-3-methylimidazole ethyl sulfate (EMIES) and water. The resulting ionic gels exhibit a microphase separation structure along with exceptional mechanical strength (6.18 MPa), favorable ionic conductivity (0.15 S/m), remarkable tensile toughness (670 %), outstanding moldability, high optical transparency, and efficient large-scale preparation. Furthermore, ionic gels demonstrate superior ionic conductivity and can be engineered into both soft and hard strain sensors tailored for diverse applications. This paper presents a straightforward and efficacious approach for obtaining superior-quality and functional ionic gels.