A Highly Transparent, Underwater Self-Healing, Self-Adhesive, and Recyclable Supramolecular Eutectogel for Liquid Metal Encapsulation

One-step preparation of supramolecular eutectogels (SEGs) with water resistance, transparency, underwater self-healing, self-adhesion, and full recyclability using a simple and green process is intriguing but also challenging. Here, a novel SEG is prepared by in situ ring-opening polymerization of thioctic acid (TA) in a polymerizable hydrophobic deep eutectic solvent (DES). Further depolymerization of poly(TA) is achieved by synergistic interaction between the eutectic monomer and hydrophobic DES components, resulting in the SEG exhibiting highly optical transparency, extreme stretchability, and full recyclability. Moreover, the hydrophobic interaction and multiple dynamic interactions enable the self-healing and self-adhesive processes of SEG to be easily realized even underwater. Given these comprehensive capabilities, SEGs are used as external encapsulation layers for liquid metals to prepare stretchable composite wires for underwater electromyographic signal monitoring. The methodology provides a new route for recyclable integrated electronic components and green underwater adhesives.