Effects of stabilization temperatures on electro-optic characteristics of polymer-stabilized optically isotropic liquid crystals

Polymer stabilization of a single cholesteric LC mixture with a short pitch has been performed at different temperatures near the transition from nematic to isotropic phases. Depending on the stabilization temperatures, the LC/polymer composites under applied electric field exhibit significantly different electro-optic properties. Although, in all cases, optical birefringence is induced by the Kerr effect from initially optically isotropic LC states, phase structures, morphology of the stabilizing polymer networks, and electro-optic properties such as contrast ratio, hysteresis and threshold voltage of the cells, crucially rely on the stabilization temperatures. Based on the polymer morphology and electro-optic characteristics, we conjecture that the stabilization temperature affects the nanoscopic structure of LC phase prior to and consequently after the polymer stabilization. (C) 2010 Elsevier B.V. All rights reserved.