Multifunctional Smart Textronics with Blow-Spun Nonwoven Fabrics

Abstract

Here, the fabrication of nonwoven fabric by blow spinning and its application to smart textronics are demonstrated. The blow-spinning system is composed of two parallel concentric fluid streams: i) a polymer dissolved in a volatile solvent and ii) compressed air flowing around the polymer solution. During the jetting process with pressurized air, the solvent evaporates, which results in the deposition of nanofibers in the direction of gas flow. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) dissolved in acetone is blow-spun onto target substrate. Conductive nonwoven fabric is also fabricated from a blend of single-walled carbon nanotubes (SWCNTs) and PVdF-HFP. An all-fabric capacitive strain sensor is fabricated by vertically stacking the PVdF-HFP dielectric fabric and the SWCNT/PVdF-HFP conductive fabric. The resulting sensor shows a high gauge factor of over 130 and excellent mechanical durability. The hierarchical morphology of nanofibers enables the development of superhydrophobic fabric and their electrical and thermal conductivities facilitate the application to a wearable heater and a flexible heat-dissipation sheet, respectively. Finally, the conductive nonwoven fabric is successfully applied to the detection of various biosignals. The demonstrated facile and cost-effective fabrication of nonwoven fabric by the blow-spinning technique provides numerous possibilities for further development of technologies ranging from wearable electronics to textronics.