Stretchable and Conductive Polymer Films Prepared by Solution Blending

Stretchable and conductive materials can have important application in many areas, such as wearable electronics and healthcare devices. Conducting polymers have very limited elasticity because of their rigid conjugated backbone. In this work, highly stretchable and conductive polymer films are prepared by coating or casting aqueous solution of poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) and a soft polymer, including poly(ethylene glycol), poly(ethylene oxide), or poly(vinyl alcohol). The soft polymers can greatly improve the stretchability and the conductivity of PEDOT:PSS. The elongation at break can be increased from 2% up to 55%. The soft polymers can also enhance the conductivity of PEDOT:PSS from 0.2 up to 75 S cm–1. The conductivity is further enhanced by adding dimethyl sulfoxide (DMSO) or ethylene glycol (EG) into the aqueous solutions of the polymer blends. Polymer blends with an elongation at break of close to 50% and a conductivity of 172 S cm–1 are attained.