Nematic phases in achiral unsymmetrical four-ring bent-core azo compounds possessing strongly polar cyano and nitro moieties as end substituents: Synthesis and characterization

被引：26

作者：

Debnath, Somen ^{[1
]}

Mohiuddin, Golam ^{[1
]}

Turlapati, Srikanth ^{[1
]}

Begum, Nazma ^{[1
]}

Sarkar, Dipika Debnath ^{[1
]}

Rao, V. S. Nandiraju ^{[1
]}

机构：

[1] Assam Univ, Dept Chem, Silchar 788011, India

来源：

DYES AND PIGMENTS | 2013年 / 99卷 / 02期

关键词：

Banana; Azo dye; Polar; Nematic; Cybotactics; Cis-trans isomerization; SMECTIC LIQUID-CRYSTALS; HOMOLOGOUS SERIES; TRANSITION; MESOMORPHISM; MESOGENS; BEHAVIOR;

D O I：

10.1016/j.dyepig.2013.05.029

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

Achiral unsymmetrical four-ring bent-core liquid crystals with strongly polar cyano and nitro moieties as substituents at one end and alkyloxy group (butyl to dodecyl) at the other end have been synthesized by a simple and straight forward synthetic method. The four phenyl rings are connected through azo, ester and imine linkages respectively and bent unit is derived from 3-aminobenzoicacid with 2-methyl substituent in the transverse direction of the molecule. The molecular structure characterization is consistent with elemental and spectroscopic analysis data. The materials thermal behaviour and phase characterization have been investigated by differential scanning calorimetry and polarizing optical microscopy. All the compounds exhibit enantiotropic nematic phase over a wide temperature range. The light induced cis-trans isomerization is also discussed. (C) 2013 Elsevier Ltd. All rights reserved.

引用

页码：447 / 455

页数：9

共 58 条

[11] Ferroelectric Response and Induced Biaxiality in the Nematic Phase of a Bent-Core Mesogen [J].