Eur. Phys. J. E (2009) 30: 265-274
https://doi.org/10.1140/epje/i2009-10518-3

Regular Article

Dielectric spectroscopy of Polymer Stabilised Ferroelectric Liquid Crystals

School of Physics and Astronomy, University of Manchester, Schuster Laboratory, Oxford Road, M13 9PL, Manchester, UK

^* e-mail: sarabjot.kaur@manchester.ac.uk

Received: 26 May 2009
Revised: 24 July 2009
Accepted: 9 September 2009
Published online: 11 October 2009

Abstract

Dielectric measurements were carried out in the frequency range from 20Hz to 500kHz on Polymer Stabilised Ferroelectric Liquid Crystals (PSFLCs). Polymerisation in the Smectic A* (Sm A*) and the Smectic C* (Sm C*) phase at equal polymer concentration results in a dielectric strength which is nearly twice the value in the latter case. An increase of the polymer concentration results in a decrease of the dielectric strength and an increase in relaxation frequency. The textural morphology and transmission intensity due to the residual birefringence of the polymer network in the isotropic phase, revealed a correlation between the interactions of the liquid crystal molecules with the polymer network. Results for polymerising in the tilted Sm C* phase with a large bias field are also reported which show that the structure of the phase in which the system was polymerised affects the dielectric properties. The observed differences in dielectric behaviour can be explained by the polymer network morphology formed due to the interplay of phase and temperature on the stabilised ferroelectric liquid crystal materials.