The study of magnetic and non-magnetic nanoparticles to improve thermodynamic and electrical properties of liquid crystals are able liquid crystal displays

Document Type : Original Article



In this present study, was investigated the phase transition of pentylcyanobiphenyl (5CB) 55% and heptylcyanobipheny (7CB) 45% (E5CN7) doped with 1% TiO2 and Fe3O4 by using Differential Scanning Calorimetry (DSC). The Nematic-Isotropic (N-I) phase transition temperature shifted to lower temperature 1.04 and 1.41 K for TiO2 and Fe3O4 respectively. For the understanding of effective parameter on the N-I phase transition temperature was used mean field theory. Was observed good agreement between theoretical and experimental resulted. In the second was studied of electrical behavior of   E5CN7 in present both of NPs, the results shows value of diffusion and ion mobility reduce in present of NPs (specially of Fe3O4). Also the resistance is reduce and conductivity increases.  


Main Subjects

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]25[ بقایری، مهدی; ملکی، بهروز; فرهادی، سمانه، دانشگاه سمنان، مجله اندیشه علوم، شماره 38 (1395)، 101.