Acrylic Acid/Sulfobetaine Methacrylate-Based Deep Eutectic Solvent Hydrogel for Flexible Sensing Applications

Ionic conductive gels have received significant interest for on-skin electronic devices. However, these gels often struggle with mechanical properties, fatigue resistance, and environmental adaptability (such as dehydration in open air and freezing at low temperatures), which restricts their use in gel-based electronics. Polymer–deep eutectic solvent (DES) gels offer a promising solution to these challenges. In this work, we present a DES-based hydrogel based on poly(vinyl alcohol) (PVA) and a DES synthesized from acrylic acid (AA) and sulfobetaine methacrylate (SBMA), with the inclusion of cobalt ions (Co), thereby addressing the aforementioned limitations. ASPC (AA/SBMA/PVA/Co) DES hydrogel demonstrates excellent stretchability (>3000%), robust mechanical properties, and good environmental resilience. We believe that the ASPC DES hydrogels are ideal candidates for on-skin healthcare monitoring applications.