An Environmentally Stable, Adhesive MXene/Urushiol Dual-Network Hydrogel for Multifunctional Sensing and Electromagnetic Shielding Applications

To address the performance limitations of hydrogels in complex and demanding environments, this study focuses on transforming them from single-function materials into integrated intelligent systems. A multifunctional AUMG 6 hydrogel was developed by integrating a urushiol-acrylamide (UH-AAm) copolymer and MXene nanosheets into a water-glycerol binary solvent. The synergistic dual-network structure, which is reinforced by intercalation-enhanced physical interlocking with MXene, exhibited robust mechanical properties, including high elongation (520%), tensile strength (103 kPa), toughness (314 kJ/m 3 ), and compressive strength (1246 kPa). The hydrophobic alkyl chains and adhesive catechol groups enabled strong adhesion to both dry and wet substrates (e.g., wood, glass, silicone) and across diverse chemical environments. The low-volatility water-glycerol medium significantly suppressed dehydration, maintaining stable adhesion for 90 days and a watertight seal for 7 months under ambient laboratory conditions. The embedded MXene conductive network offered robust electromagnetic interference shielding (41 dB) and high-sensitivity detection of human motion and vocal vibrations. Notably, the hydrogel retained flexibility after 60 days of storage at −20 °C, 20 °C, and 60 °C, and retained sensing reliability after 60 days of storage at −20 and 60 °C. This study presents a hydrogel system with durable mechanical, adhesive, electromagnetic, and sensing performance, demonstrating promising potential in applications such as extreme-environment electronics, underwater adhesion, EMI shielding, health monitoring, and intelligent voice recognition.