Optical Transmission and Conductivity of Nematic Liquid Crystals Containing Dispersed Multiwall Nanotubes

Abstract

For nematic liquid crystals (LC) with small (0.01–0.15 wt%) concentration of multiwall nanotubes (NT) dispersed therein, optical transmission and electric conductivity were measured as a function of temperature. Characteristic changes in transmission at the nematic-isotropic phase transition temperature have been noted, suggesting that NT dispersed in the LC matrix behave in a manner similar to that of the conventional non-mesogenic dopants. This picture is supported by the electrical conductivity data. The electrical conductivity increased noticeably within ∼0.01–0.1 wt% range of NT concentrations in the LC matrix, and a marked difference in the measured electrical conductivity values for the LC matrices of different polarity (e.g., cyanobiphenyl and azoxy) was observed.