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

摘要

Physical eutectogels are appealing materials for technological devices dueto their superior ionic conductivity, thermal and electrochemical stability,non-volatility, and low cost. Nevertheless, current physical eutectogels aresuffering from weak mechanical strength and toughness. Here, taking advantageof the distribution difference of polyvinyl alcohol (PVA) in water anddeep eutectic solvents (DESs), a simple and universal solvent-replacementapproach 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 interactionsbetween PVA chains in water, enabling PVA to crystallize to constructa uniform and robust polymer network. Consequently, the resultant PVAeutectogel exhibits record-high strength (20.2 MPa), toughness (62.7 MJ m~(–3)),and tear-resistance (tearing energy Σ42.4 kJ m~(–2)), while possessing excellentstretchability (Σ550 strain), repairability, and adhesive performance.Furthermore, this strategy is proven to be universally applicable to variousspecies of polymers, and even can be utilized to fabricate continuous andconductive eutectogel fibers, demonstrating potential as engineering materialsand wearable sensors.