Design synthesis and characterization of hydrogen bonded ferroelectric liquid crystals formed by levo tartaric acid and alkyloxy benzoic acids

Abstract

Design synthesis and characterization of Hydrogen Bonded Liquid newlineCrystals HBLC play a vital role in the development of soft materials for newlinevarious applications Especially the characterizations of Ferroelectric Liquid newlineCrystals FLC have great implication to fulfil the current challenges in display newlinedevices materials With this insight the present study is intended to design newlinesynthesize and characterize three novel series of hydrogen bonded compounds newlineincluding chiral homologues These compounds are characterized by newlinespectroscopic studies FTIR and NMR thermal studies Polarizing Optical newlineMicroscopy POM Differential Scanning Calorimetric study DSC and Optical newlinetilt angle measurements Further the variation of dielectric permittivity with newlinetemperature and dielectric relaxation studies in various mesophases are also newlinecarried out to detect the phase transition temperatures and corresponding newlineArrhenius energies The growth of selected mesophases has been studied by newlinecrystallization kinetics newlineDesign synthesis and characterization of various Hydrogen Bonded newlineLiquid Crystals HBLC have been undertaken Three series of compounds newlinenamely levo tartaric acid and pn alkoxy benzoic acid homologous series newlineLTAnBAO where n represent alkoxy carbon number dodecyl aniline and piv newlinen alkoxy benzoic acid homologous series 12A12BAO and hexadecyl aniline newlineand pn alkoxy benzoic acid homologous series 16A12BAO have been newlineisolated The synthesis route involves mixing of equimolar ratios of pn alkoxy newlinebenzoic acid and the other ingredients The first series LTAnBAO is newlineferroelectric with four compounds exhibiting various orthogonal and tilted newlinephases the latter two series 12AnBAO 16AnBAO comprise of sixteen newlinedifferent compounds exhibiting rich phase polymorphism FTIR and NMR newlinestudies on these compounds infer the formation of hydrogen bond newlineConventional phases like Cholestric Nematic Smectic C Smectic F and newlineSmectic G phases are recorded and identified with the standard textures newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline newline