Strong and Tough Physical Eutectogels Regulated by the Spatiotemporal Expression of Non‐Covalent Interactions

Physical eutectogels are appealing materials for technological devices due to their superior ionic conductivity, thermal and electrochemical stability, non-volatility, and low cost. Nevertheless, current physical eutectogels are suffering from weak mechanical strength and toughness. Here, taking advantage of the distribution difference of polyvinyl alcohol (PVA) in water and deep eutectic solvents (DESs), a simple and universal solvent-replacement approach is proposed to regulate the spatiotemporal expression of intra/interpolymer interactions to prepare strong and tough physical eutectogels. The exchange of DESs with water can restrengthen the weakened interactions between PVA chains in water, enabling PVA to crystallize to construct a uniform and robust polymer network. Consequently, the resultant PVA eutectogel exhibits record-high strength (20.2 MPa), toughness (62.7 MJ m(-3)), and tear-resistance (tearing energy sigma 42.4 kJ m(-2)), while possessing excellent stretchability (sigma 550% strain), repairability, and adhesive performance. Furthermore, this strategy is proven to be universally applicable to various species of polymers, and even can be utilized to fabricate continuous and conductive eutectogel fibers, demonstrating potential as engineering materials and wearable sensors.