The role of conductive dopants in polymer cholesteric liquid crystals

Abstract

Abstract Variety of conductive dopants were used to modify the electric properties of polymer cholesteric liquid crystals. Different types of carbon blacks, carbon nanotubes, as well as metallic particles were used as conductive dopants in this work. All of them affected the conductivity of the polymer matrix, but at different dopant concentrations. The percolation threshold behaviour of used dopants in the polymer host showed pronounced dependence on the dopants’ particle size and particle shape anisotropy. For instance, the higher the aspect ratio of carbon-based dopant particles (aspect ratio = length : diametar), the lower the percolation threshold; while increase in metallic dopants' diameter yielded higher percolation threshold of polymer composition.

Keywords

• polymer cholesteric liquid crystals, conductive dopants, carbon black, carbon nanotubes, percolation threshold