Ion–Dipole Anchoring Enables Exceptional Hydration Stability in Polyquaternium-10/Poly(ionic liquids) Hydrogels for Flexible Electronics

A fundamental obstacle in developing high-performance ionic conductive hydrogels (ICHs) is the inherent trade-off between ionic conductivity and long-term hydration stability. Herein, we demonstrate ion–dipole anchoring as a powerful strategy to overcome this limitation. This strategy is realized in a semi-interpenetrating network hydrogel composed of polyquaternium-10 (PQ-10) and polymerized ionic liquid (PIL) via electron beam irradiation (PQ-10/PIL ICH). The ion–dipole anchoring effect arises from the strong specific interactions between the imidazolium cation (VEIM + ) and bromide anions (Br – ) from the PIL and water molecules, which drastically reduce water activity and suppress evaporation. Crucially, this anchoring mechanism operates independently within the continuous PIL phase, preserving high ionic conductivity (5.02 S m –1 at 25 °C) while enabling exceptional water retention (83.04% after 60 days). The PQ-10/PIL ICH demonstrates outstanding performance in flexible sensing and solid-state supercapacitors, retaining 85.00% capacitance after 10,000 cycles. This work establishes ion–dipole anchoring as a foundational design principle for creating durable and high-performance flexible electronic devices.