Laboratoire de Dynamique et Structure des Matériaux Moléculaires, Equipe de Thermophysique de la Matière Condensée URA CNRS 801, Université du Littoral Quai Freycinet 1 BP 5526 F-59379 Dunkerque Cedex 1 France
The Modulated Differential Calorimetry (MDSC) is applied to the determination of the reversibility in the cholesteryl chloride, which presents a cholesteric monotropic phase between the isotropic and crystalline states. The experimental modulation parameters that govern this method i.e. frequency, amplitude and heating/cooling rate, are determined. MDSC curves and complementary thermomicroscopical observations assign melting, crystallization and liquid cholesteric transition as ‘non reversing’, and clarification as ‘reversing’.