Effects of the addition of anionic surfactant during template polymerization of conducting polymers containing pedot with sulfonated poly(imide) and poly(styrene sulfonate) as templates for nano-thin film applications

Herein, the addition of an anionic surfactant, sodium dodecyl sulfonate (SDS), during the template polymerization of conducting polymers to improve the nano-thin films properties was investigated. In order to compare the effects, three methods of addition SDS were demonstrated: addition of SDS during template polymerization, addition after template polymerization, and addition of both during and after template polymerization. Sodium dodecyl sulfonate (SDS) was utilized as a stabilizer and a dopant for the polymerization of 3,4-ethylenedioxythiophene (EDOT) with two different templates, sulfonated poly(imide) (SPI) and polystyrene sulfonate (PSS). The addition of SDS during polymerization of both PEDOT-SPI and PEDOT-PSS was more effective in stabilizing particles against coagulation, significantly reducing the sizes of conducting particles, forming stable spherical particles, and enhancing thermal stability and conductivity. Evidence from FTIR measurements indicated that molecular interactions between SDS and PEDOT chains resulted in the decrease in distortion of the structures and in the effectiveness of doping of the PEDOT chains. TEM and TGA analyses further showed that SDS molecules were intercalated in conducting particles when they were added during polymerization. The addition of SDS during template polymerization of PEDOT demonstrated a greater effect on colloid stability and intercalation doping than that of the addition of SDS after polymerization, resulting in significant conductivity improvements of PEDOT-SPI and PEDOT-PSS films.