Liquid crystalline properties of 4‐hexyloxybenzylidene‐4′‐alkyloxyanilines

Abstract

The liquid-crystalline polymorphism of the homologous series of 4-hexyloxybenzylidene-49-alkyloxyanilines is investigated. Basing on the polarization microscopy (POM, TOA), the DSC calorimetry and miscibility studies the following mesophases were detected: nematic, smectic A, smectic C and smectic I. The phase diagrams of the compounds of these series with 4-hexyloxybenylidene-49-pentylaniline (as the standard of mesophases) show induction of the smectic F mesophases. Their dependence on the alkyl chain length and mole fraction is shown.

Synthesis, Characterization and Phase Transition Studies on Some N-(4-Butyloxy Benzylidene)-4-Alkoxy Anilines, 4O.Om Compounds - A Dilatometric Study

“…The following observations are made from the earlier studies on Shiff's base compounds [2][3][4][7][8][9][10].When the oxygen atom is on the left side of the rigid core (nO.m) compounds, generally, the clearing temperatures are below 100O C, no compound exhibits smectic-I phase and only few compounds show smectic-A to smectic-C (AC) transition.When the oxygen atom is on the right side of the rigid core (n.Om), the situation is more or less same as the case of nO.m compounds except in the exhibition of phase variants. When the oxygen atom is on both sides of the rigid core (nO.Om), the clearingtemperatures are elevated to more than 100O C, and we see the presence of nematic phase even in compounds with high alkoxy chain number and the exhibition of phases such as smectic-I and the phase transitions such as smectic-A to smectic-C((SmA-SmC) and smectic-C to smectic-I (SmC-SmI) andWhen the oxygen atom is quenched from the molecular moiety (n.m), the clearing emperatures are lowered to around 50O C, the liquid crystalline nature in some cases goes below room…”

Thermothropic azomethines and polyazomethines showing liquid crystalline properties

“…W literaturze w ci¹gu ostatnich ooemiu lat mo¿na zna-leŸae nieliczne doniesienia dotycz¹ce ciek³okrystalicznych azometin symetrycznych z jednym wi¹zaniem iminowym [20][21][22]. W azometinach przedstawionych wzorami (II)-(IV) obserwowano, w zale¿nooeci od budowy chemicznej zwi¹zku, fazy N, SmA, SmC lub N* [20][21][22].…”

“…Godzwon i wspó³pr. [21] zaobserwowali, i¿ azometina przedstawiona wzorem (III), w której jest obecny mezogen z dwoma pieroecieniami benzenowymi po³¹czonymi grup¹ HC=N-oraz dwa ³añcuchy alkoksylowe, wy-kazywa³a istnienie fazy smektycznej typu C w temp. 114.1 o C.…”

The Influence of Oxygen on Mesomorphic Behavior of Benzylidene Anilines—The Effect of End Chain

“…The scientific research devoted to liquid-crystalline materials has expanded greatly during the last several years. Of particular importance is the organic synthesis aspect to study the chemical, structural, and mesomorphic properties of compounds [2][3][4]. The mesomorphic behavior of liquid crystals is basically dependent on their molecular structures in which a slight change in their molecular geometry may bring about considerable change in their mesomorphic properties [5].…”