Scalable and Facile Preparation of Highly Stretchable Electrospun PEDOT:PSS@PU Fibrous Nonwovens toward Wearable Conductive Textile Applications

Flexible and stretchable conductive textiles are highly desired for potential applications in wearable electronics. This study demonstrates a scalable and facile preparation of all-organic nonwoven that is mechanically stretchable and electrically conductive. Polyurethane (PU) fibrous nonwoven is prepared via the electrospinning technique; in the following step, the electrospun PU nonwoven is dip-coated with the conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). This simple method enables convenient preparation of PEDOT:PSS@PU nonwovens with initial sheet resistance in the range of 35-240 Omega/sq (i.e., the electrical conductivity in the range of 30-200 S m(-1)) by varying the number of dip-coating times. The resistance change of the PEDOT:PSS@PU nonwoven under stretch is investigated. The PEDOT:PSS@PU nonwoven is first stretched and then released repeatedly under certain strain (denoted as prestretching strain); the resistance of PEDOT:PSS@PU nonwoven becomes constant after the irreversible change for the first 10 stretch release cycles. Thereafter, the resistance of the nonwoven does not vary appreciably under stretch as long as the strain is within the prestretching strain. Therefore, the PEDOT:PSS@PU nonwoven can be used as a stretchable conductor within the prestretching strain. Circuits using sheet and twisted yarn of the nonwovens as electric conductors are demonstrated.