Preparation of Flexible Conductive Films Possessing High Elasticity and Excellent Mechanical-Electrical Synergistic...

Integrating high elasticity, high-fidelity electromechanical transduction, and long-term operational stability under dynamic mechanical deformation has become a fundamental scientific challenge to develop ultrathin conductive rubber films for the field of flexible electronics. In this work, hydrogenated nitrile butadiene rubber/single-walled carbon nanotube (HNBR/SWCNT) based rubber films with precisely controlled thickness were prepared with a wet coating process in N-methyl-2-pyrrolidone (NMP) and cyclohexanone (CYC). Results have demonstrated that NMP-derived rubber films exhibit exceptional tensile strength (22.4 MPa), outstanding cyclic durability (modulus retention >92% after 5000 cycles), and ultralow volume resistivity (0.75 kΩ·cm). Conversely, CYC-derived rubber films achieve extraordinary extensibility (EAB > 400%) but display significantly elevated resistivity (77 kΩ·cm), directly resulting from discontinuous and defect-rich SWCNT networks with poor intertube connectivity. Critically, both HNBR/SWCNT rubber films display strain-rate-independent stress-strain response over the broad range of 50-500 mm/min and retain >94% of elongation at break and >94% of electrical conductivity after 168 h thermal aging. Collectively, owing to the wide detection range (1-100% strain), high gauge factor (GF = 455), and exceptional fatigue resistance (ΔR/R0 < 5% after 5000 bending cycles), NMP-derived HNBR/SWCNT films can be integrated as the active transducing layer for the next-generation flexible strain sensors, real-time physiological monitoring patches, and intelligent wearable electronic systems.