Concentration dependences of dielectric properties at 105 Hz and 106 Hz for aqueous solutions of hydroxypropyl cellulose

The concentration dependences of dielectric properties measured at 105 Hz and 106 Hz are reported for aqueous solutions of hydroxypropyl cellulose. Phase behaviour of the solutions was also observed with a polarizing optical microscope. For solutions with concentrations well above 40 wt %, polydomain textures, including the banded texture, were observed after a prehistory of deformation. No significant discontinuous changes in the dielectric constant, εr', and loss factor, εr'', were found at the concentrations around the onset of the isotropic-cholesteric phase transition and in the biphasic region. In contrast, the steeper changes in εr' and εr'' were found at the critical concentration for the fully developed cholesteric phase transition with the polydomain textures.