Experimental investigation of phase transitions in nematic-cholesteric mixtures

Authors

  • Валерий Григорьевич Гилев (Valerij Gilev) Perm State University
  • Дарья Юрьевна Кулёмина (Darja Kulyemina) Perm State University

DOI:

https://doi.org/10.17072/1994-3598-2017-3-16-21

Abstract

Phase transitions of nematic-cholesteric mixtures of liquid crystals: solutions of cholesteryl propionate in methoxybenzylidene-butylaniline are investigated. The concentration range of cholesteric varied from 1 to 24 wt.%. The concentration range of cholesteric varied from 1 to 24 wt.%. Rheologicacal measurements were performed using a rotational viscometer Physica MCR 501, refractometric measurements – the refractometer Abbemat 550. Flow curves, temperature dependences of viscosity and refractive index, initial samples and their mixtures are measured. Determination the temperature of the transition of samples to the isotropic phase.  It is shown that the temperature dependence of the viscosity of the mixtures before and after phase transition points can be approximated by the Arrhenius equation. The dependences of the parameters of the Arrhenius equation on the concentration of cholesteryl-propionate are constructed.

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Published

2017-12-28

How to Cite

Гилев (Valerij Gilev) В. Г., & Кулёмина (Darja Kulyemina) Д. Ю. (2017). Experimental investigation of phase transitions in nematic-cholesteric mixtures. Bulletin of Perm University. Physics, (3(37). https://doi.org/10.17072/1994-3598-2017-3-16-21

Issue

Section

Regular articles

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