A high-toughness, high-strength, and highly sensitive nanocellulose-based double-network eutectogel with...

This study reports a novel double-network (DN) eutectogel (DN-PBCP-Eutectogel) designed to overcome the limitations of conventional gels in mechanical properties, environmental stability, and sensing sensitivity. The first network forms a rigid skeleton through boric acid crosslinking of cellulose nanofibers (CNF) and polyvinyl alcohol (PVA). The second network creates a flexible structure through UV-induced polymerization of a polymerizable deep eutectic solvent (PDES, composed of choline chloride, acrylic acid, and glycerol). The interpenetrating networks form a dual-network architecture featuring dynamic covalent bonds, hydrogen bonds, and chain entanglements. This imparts exceptional mechanical properties (tensile strength: 0.87 MPa; toughness: 3.67 MJ/m³), high elasticity and fatigue resistance (strength retention: 82.6%), high sensitivity (GF = 19.38), and broad environmental tolerance. Leveraging these superior properties, the gel sensor accurately detects physiological activities such as joint bending, swallowing, and coughing, while also enabling Morse code signal transmission, demonstrating its broad application potential in flexible wearable electronics.