Ultra-High Conductivity Enhancement of Robust All-Solid-State Ion Elastomers via Strain-Induced Ion Channel Alignment and Temperature-Activated Ion-Gated Release.

Abstract

Despite their potential in ionic electronics, conventional ionic conductors face critical limitations, including modest strain-modulated conductivity and restricted self-regulation under temperature variations. Here, a mechanically robust all-solid-state ionic elastomer is presented, engineered through molecular design and microphase separation. By in situ integrating polyacrylamide (PAM) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) into maleic anhydride-grafted styrene-ethylene-butylene-styrene (SEBS-MAH), a hierarchical structure with dynamic non-covalent interactions (hydrogen bonds, lithium bonds, and cation-π effects) is achieved. This design yields exceptional mechanical properties, including a tensile strength of 46.4 MPa, strain of 1066%, and toughness of 207.8 MJ m^-3, alongside outstanding recyclability and puncture resistance. Remarkably, strain-induced alignment of microphase-separated domains reduces ion transport tortuosity, enabling a 1300 times conductivity enhancement at 1066% strain. Concurrently, temperature-gated ion release from confined regions triggers a 1600 times conductivity increase at 120 °C. The elastomer maintains high conductivity (>10^-3 S m^-1) across an ultra-wide temperature range (-45-120 °C), overcoming the limitations of conventional hydrogels and ionogels. This work pioneers a dual-stimuli-responsive strategy for advanced ionic conductors, offering transformative potential in wearable electronics, soft robotics, and adaptive sensors.