PEDOT-PSS/singlewall carbon nanotubes composites

Poly(3,4-ethylenedioxythiophene)-single wall carbon nanotube (SWNT) composites were prepared via coating methods for improving electrical conductivity and flexibility, minimizing loss of transparency. Three types of surface modified SWNTs were prepared through different modification methods: carboxylated SWNT treated with nitric acid to form carboxylic acid group on their surfaces, 1-pyrenebutyric acid wrapped SWNT, and 1-pyrenebutyric acid, lithium salt wrapped SWNT. The surface modifiers had influence on the dispersion states of the SWNTs in 2-propanol. The dispersion states had influence of aggregate concentrations of surface modified SWNTs in polymer matrix, showing lower aggregate concentration for the carboxylated SWNT than those of the other surface modified SWNTs. The dispersion behaviors of SWNTs were also related with transparency and electrical resistance, and flexibility of composite films. Based on the layer-by-layer coating method, SWNT composite film properties such as thickness, transparency, and electrical conductivity could be controlled and would be a good example for improving contradictory properties.