Transparent Piezoresistive Thin-Films for Strain Sensor Applications

The recent exploit of strain sensor devices that can readily monitor human body action, has gained tremendous attention, in the field of various wearable electronics and human-machine interfaces applications. In this study, we report a facile way of forming transparent, piezoresistive composite thin-films from a mixture of conductive polymer, elastomeric polymer and surfactnat. Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), thermoplastic polyurathene (TPU), and capstone 30 are used as a conductive polymer, elastomer and surfactant, respectively. The piezoresistive performances are regulated depending on a compositon of surfactant in PEDOT:PSS-TPU composite thin films. A resistance change as high as 86.5 are obtained when the stretchable composite thin-films are stretched with a strain ranging 0.1 to 0.35, with a transparency of 89.1 % at 550 nm.