Co-deformable Conductive Composite Films via Elasticity-Driven Reversible Dynamic Bonds

The booming development of flexible electronics urgently calls for flexible conductive materials with outstanding mechanical strength, desirable elastic recovery, and reliable conductivity. Herein, a UV-curable polyacrylate conductive composite film (polyacrylate-AA-ChCl, PAAC) is rationally designed, featuring enhanced elastic recovery endowed by reversible hydrogen bonds. A polyacrylate (PA) film is first fabricated via UV-initiated polymerization using acrylate monomers and a vinyl-terminated polyurethane prepolymer as the cross-linker, exhibiting high transparency (>90%), solvent resistance (>72 h), favorable mechanical strength, and folding resistance. Subsequently, a polymerizable deep eutectic solvent (PDES)-specifically, acrylic acid/choline chloride (AA/ChCl)-was incorporated. This endows the composite with stable ionic conductivity while preserving its original mechanical properties. The resultant PAAC composite as a flexible strain sensor achieves excellent compatibility between components, outstanding mechanical durability (14.2 MPa and 735%), reliable conductivity (GF = 1.58) under deformation, and a low glass transition temperature (Tg = 4.5 °C). This work proposes a facile, scalable, and high-performance strategy for fabricating flexible conductive composites, which offers novel insights into the advancement of flexible electronics, wearable devices, and eco-friendly functional materials.