Stretchable Fiber Mat Strain Sensor with Surface Hetero-Modulus Microstructure Fabricated by Weak Solvent Swelling Effect
With the increasing demand of flexible wearable electronic devices,it is of great significance to fabricate strain sensors with high mechanical elasticity and excellent electro-mechanical response.Among them,bilayer structured resistive strain sensors have recently aroused more attention thanks to their superior strain sensing performance.However,in the practical application,the conductive layer will induce the generation of irreversible penetrating micro-cracks,resulting in the exponential increase of resistance under strain to limit its application in practical scenarios.Based on the"microcrack"sensing mechanism,high-modulus carboxylated polystyrene microspheres(PSNSs)were introduced into the surface of electrospun thermoplastic polyurethane(TPU)fiber mats with aligned nanofibers by coaxial electrospinning to form hetero-modulus microstructures.Such a hetero-modulus microstructure on the fiber surface can effectively dissipate local strain during stretching,cutting off the propagation of penetrating microcracks during strain loading.The strain sensing behavior of the hetero-modulus materials could be adjusted by adjusting the concentration and ratio of solvents for the PSNSs suspensions,as well as the physical/chemical interactions among fibers,PSNSs,and silver nanoparticles.The as-prepared conductive composite films can achieve a fast response and recovery(49.7 ms/62.5 ms),maintain a linear response with high strain sensitivity(gauge factor,GF=257)over a relatively wide strain range(0～30％).
万方数据
维普
