INVESTIGATION OF DIELECTRIC PROPERTIES OF MBBA-5CB NEMATIC LIQUID CRYSTAL STRUCTURES

Authors : Gülnur ÖNSAL

Pages : 49-53

Doi:10.22531/muglajsci.1198432

View : 14 | Download : 7

Publication Date : 2022-12-30

Article Type : Research Paper

Abstract :The dielectric anisotropy insert ignore into journalissuearticles values(Δε\`); is the response of the LC molecules to an applied electric field. In this study, the dielectric properties of 4-pentyl-4\`-cyanobiphenyl insert ignore into journalissuearticles values(5CB); and N-insert ignore into journalissuearticles values(4-methoxybenzylidene);-4-butylaniline insert ignore into journalissuearticles values(MBBA); nematic liquid crystals with positive and negative dielectric anisotropy were investigated in detail. In addition, a structure with zero dielectric anisotropy was obtained by mixing MBBA and 5CB liquid crystals in certain rate insert ignore into journalissuearticles values(1:0.02);. The behavior of the samples under 0V and 20V voltages was investigated in detail. Dielectric measurements were made with dielectric spectroscopy technique, which is a powerful method to investigate the molecular interaction mechanisms of liquid crystal materials, at a frequency of 1 kHz-10 MHz and a voltage of 0-20 V at room temperature. Some important parameters such as dielectric anisotropy insert ignore into journalissuearticles values(Δε\`);, relaxation frequency insert ignore into journalissuearticles values(f R );, relaxation time insert ignore into journalissuearticles values(τ); were determined for the samples. When electric field is applied to nematic liquid crystals, it is seen that, depending on the voltage, the relaxation frequency decreases, and the relaxation time increases.
Keywords : Nematic liquid crystal, 5CB, MBBA, dielectric properties, dielectric anisotropy