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arXiv · 2411.02060

Crystallization kinetics of equimolar liquid crystalline mixture and its components

Aleksandra Deptuch·Anna Paliga·Anna Drzewicz·Marcin Piwowarczyk·Magdalena Urbańska·Ewa Juszyńska-Gałązka
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Abstract

The new equimolar mixture comprises liquid crystalline compounds MHPOBC and partially fluorinated 3F2HPhF6. The phase sequence of the mixture is determined by differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, and broadband dielectric spectroscopy. The enantiotropic smectic A*, C*, and CA* phases are observed for the mixture. Only partial crystallization of the mixture is observed during cooling at 2-40 K/min and the remaining smectic CA* phase undergoes vitrification. In contrast, the crystallization of the pure components is complete or almost complete for the same range of cooling rates. The kinetics of the non-isothermal and isothermal crystallization of the mixture and pure components are investigated by differential scanning calorimetry. The non-isothermal data are analyzed by the isoconversional method, while the isothermal data are analyzed using the Avrami model. Typically, the nucleation-controlled crystallization kinetics are observed.

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Aleksandra Deptuch, Anna Paliga, Anna Drzewicz, Marcin Piwowarczyk, Magdalena Urbańska, Ewa Juszyńska-Gałązka. 2024-11-04. Crystallization kinetics of equimolar liquid crystalline mixture and its components. https://doi.org/10.3390/app142411701

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