Alignment and reorientation in nematic liquid crystals doped with red dye and carbon nanotube

摘要

Four different dyes (Methyl red, Disperse red 1, 13 and 60) were separately doped to each of four different nematic liquid crystals (E7, E8, E63 and ZLI-1132). Their solubilities, textures, phase transition temperatures and order parameters were determined. At the second stage, single-walled nanotubes in a small amount were separately added to each of these solutions, and the experiments were repeated as similar to previous ones. The solubility of dyes was sufficient for using in experiments. When adding dyes and nanotubes, an appreciable change in textures of liquid crystals was not observed. The phase transition temperatures stayed within the limitations required. The changes observed in order parameters depending on the voltage were very small. The highest value of order parameter (0.77) was attained when co-using red 60 dye and nanotube as dopants in the liquid crystal E63.