STUDY ON PHASE TRANSITION FEATURES AND INFRARED SPECTROSCOPY OF 3OCB LIQUID CRYSTAL

Year 2021, , 18 - 23, 31.12.2021

Atilla Eren Mamuk

https://doi.org/10.22531/muglajsci.926980

Abstract

In the study, some physical properties of the 3OCB liquid crystal belonging to the cyanobiphenyl group, which is frequently used in dimeric molecules and eutectic mixtures, were investigated. In this context, its optical properties in different temperature interval have been investigated. As a result of optical measurements, it was determined that 3OCB exhibited a monotropic mesophase and that the phase range of the mesophase was determined. In addition, it was observed that a heterophase region appeared in the liquid crystalline isotropic phase-nematic mesophase transition. Morphological analysis of the mesophase and heterophase region was also performed. Also, by performing calorimetric measurements, how the relevant liquid crystal phase interval changes in bulk state was compared with the results obtained from optical measurements. Information about the 3OCB's dominant vibration bands was obtained by performing infrared spectroscopic measurements. The infrared spectroscopy of 3OCB, which is frequently used in industry and scientific studies, has been performed to provide information about the functional groups and structure of the molecule.

Keywords

Liquid crystals, monotropic mesophase, optic, DSC, FT-IR

Thanks

The author would like to acknowledge the technical support of The Center of Research Laboratories, Muğla Sıtkı Koçman University.

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