Innovative elastic and flexible conductive PEDOT:PSS composite films prepared by introducing soft latexes

Innovative elastic and flexible conductive composite materials PEDOT:PSS/P(BA–St) and PEDOT:PSS–PBA were prepared by two approaches based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). In the first part, PEDOT:PSS/P(BA–St) was prepared by blending various soft poly(n-butyl acrylate–styrene) (P(BA–St)) latexes into a PEDOT:PSS conductive dispersion. The PEDOT:PSS conductive dispersion was prepared via oxidative polymerization of EDOT, and the soft P(BA–St) latexes were synthesized by emulsion polymerization using various types of surfactants. In the second part, poly(styrenesulfonate) (PSS) served as a surfactant to synthesize poly(styrenesulfonate)–poly(butyl acrylate) (PSS–PBA) soft latex viaemulsion polymerization. Then, the PEDOT:PSS–PBA dispersion was prepared by using the PSS–PBA soft latex as a polymeric template to polymerize EDOT. The glass transition temperature (Tg) and particle size of P(BA–St) and PSS–PBA were measured. The optoelectronic properties of the conductive PEDOT:PSS/P(BA–St) and PEDOT:PSS–PBA films such as transmittance, surface resistance, and UV-vis absorbance were investigated. According to the elongation measurement, the fabricated PEDOT:PSS/P(BA–St) elastic film containing a P(BA–St) content as high as 83 wt% showed a high value of 97% elongation, while possessing good film conductivity (63 S cm−1) and superior transmittance (93%). On the other hand, the fabricated PEDOT:PSS–PBA flexible film containing 13 wt% PBA showed a low surface resistance increment (R/R0 < 1.2) after two steps of bending test, while maintaining superior conductivity (300 S cm−1) and high light transmittance (>80%).