Surface Tension of Cholesteric Liquid Crystals: Cholesteryl Myristate

Abstract

Abstract It has been suggested that the surface region of ordered liquids and, in particular, liquid crystals may extend well into the bulk phase.1 The surface tension of such materials could be expected to reflect changes in bulk properties and should be sensitive to mesophase transitions. In this study the surface tension of cholesteryl myristate was measured as a function of continuously varying temperature. On cooling into the cholesteric phase, the surface tension exhibits a steep rise of up to 10 dynes/cm and then falls back abruptly before the cholesteric-smectic transition. In the heating mode, the surface tension of the cholesteric phase was relatively independent of temperature. Similar anomalies which are dependent on the direction of thermal change have been reported for the viscosity of cholesteric esters.