Dielectric and DSC Studies of the Bicomponent Systems with Induced Antiferroelectric Phase Comprising Cyano Terminated Compounds

Abstract

Phase transitions in pure compounds with cyanoacetyloxyalkoxy groups in terminal chain (2) and second compound comprising alkanoyloxyalkoxy groups (1) and their bicomponent mixture have been studied by optical microscopy, differential scanning calorimetry (DSC) and dielectric spectroscopy. The temperatures, enthalpies of phase transitions and Cp values as a function of temperature were determined for such system by DSC method (Differential Scanning Calorimetry). Dielectric spectroscopy confirmed the presence of induced antiferroelectric phase in mixtures. The Goldstone-mode and the soft-mode relaxation process were observed for SmC* phase and also the low frequency P_L and high frequency P_H modes, which are typical for antiferroelectric phase.

Keywords:

• cyano compounds
• dielectric properties
• DSC measurements
• induced antiferroelectric phase
• liquid crystals

Acknowledgments

This work was carried under N20402931/0512 PBS 765 projects.