Journal of Thermal Analysis and Calorimetry | 2021
Calorimetric study of smectic x* and validation of dynamic memory in ferroelectric binary complexes
Abstract
Calorimetric studies of ferroelectric liquid crystalline binary mesogens obtained by mixing precursors namely Acid-Dextro Tartaric (ADT) with either benzoic acid-heptyloxy (7BAS) or benzoic acid-octyloxy (8BAE) abbreviated as ADT\u2009+\u20097BAS and ADT\u2009+\u20098BAE, respectively, in predetermined molar ratios to develop 10 binary mesogens. ADT\u2009+\u20098BAE and ADT\u2009+\u20097BAS are treated as X and Y, and 10 proportions of the binary complexes studied are X\u2009=\u200995: Y\u2009=\u20095, X\u2009=\u200990: Y\u2009=\u200910, X\u2009=\u200980: Y\u2009=\u200920, X\u2009=\u200970: Y\u2009=\u200930, X\u2009=\u200960: Y\u2009=\u200940, X\u2009=\u200950: Y\u2009=\u200950, X\u2009=\u200940: Y\u2009=\u200960, X\u2009=\u200930: Y\u2009=\u200970, X\u2009=\u200920: Y\u2009=\u200980 and X\u2009=\u200910:Y\u2009=\u200990, respectively. The objective of this research was to investigate the enhancement in the growth of sm X* phase thermal width as the molar ratio of Y is altered progressively in the binary complexes. In the above binaries, the phases namely cholesteric, smectic (C*, X* and G*) are confirmed by corresponding optical textural studies. Phase diagram is constructed with polarizing optical microscopic study coupled with DSC phase analysis. Dielectric hysteresis with applied field yielded information about dynamic memory in ferroelectric binary complexes. Specific heat across various phase transitions in selected mesogens is presented.