Nanoliquid Crystals: A Study of Permeability and Optical Measurements in Nematic Phase

Abstract

SummaryLiquid crystal (LC) materials refer to the fourth state of matter that posses dual property of crystals and liquids. Their anisotropic physical properties (characteristic of its crystalline nature) and the inherent surface alignment (to the substrate) tendency (characteristic of its fluidity) are extensively exploited to design LC based electro‐optic devices.In recent times, hydrogen bonded ferroelectric liquid crystals [HBFLC] reported in literature, are designed and synthesized from materials selected on the basis of their molecular reorganization and self assembly capability. The applicational aspects and commercial viabilities made many research groups work on this hydrogen bonded ferroelectric liquid crystals. A novel HBFLC has been synthesized. Hydrogen bond is formed between chiral non mesogen ingredient (S)‐1, 2‐chloro‐3‐(4‐hydroxy) phenylpropionic acid (CTy) and mesogenic p‐n‐decyloxybenzoic acid (10BAO). Small amount of multiwall carbon nanotubes is dispersed in the CTy +10BAO complex. Salient feature of the present work is observation of a field induced transitions in nematic phase pertaining to nano dispersed CTy +10BAO complex. This phenomenon has been confirmed by optical textures of polarizing optical microscopic (POM) studies for the first time through dielectric studies. In nematic phase of nano dispersed CTy + 10BAO, four threshold electrical field values are noticed which in turn contributed to four new phases (E1, E2, E3 and E4) induced by electric field and on further enhancement of the applied field it has been observed that the mesogen behaves like a optical modulator. This phenomenon may be used to design optical modulator, optical shutter and efficient optical memory devices.