Ionic Conductive Elastomers with Enhanced Mechanical Properties and Applications in Triboelectric Nanogenerators

Liquid-free ionic conductive elastomers (ICEs) exhibit ideal qualities for soft devices, including high stretchability, conductivity, and transparency. In this study, a series of ICEs is developed using polymerized acrylamide (AAm) and 4-acryloylmorpholine (ACMO) as the solid network and an ionic liquid (IL), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, serving as the ionic conductor. The ions are predominantly hosted within the ACMO segments, resulting in an ionic conductivity of 0.27 mS/cm. The mechanical properties can be tuned by adjusting the molecular fraction of the monomers and the IL content. An optimized formulation, P(AAm0.2-co-ACMO0.8), achieves a wide range of mechanical properties, including tensile strength (1.05–4.17 MPa), Young’s modulus (3.08–64.78 MPa), and elongation-at-break (264–508%). The AAm segments, which facilitate energy dissipation through abundant hydrogen bonding, contribute to a high toughness of 8.84 MJ/m3. The ICEs also exhibit self-healing ability, a high decomposition temperature of 305 °C, and excellent adhesive strength to metals and glass. When integrated into triboelectric nanogenerators, these ICEs demonstrate stable performance, highlighting their potential for advanced soft ionotronic applications.