Thin Solid Films, Vol.517, No.4, 1362-1366, 2008
Thermotropic liquid crystalline amphiphilic materials with hydrophilic groups at both terminals
We synthesized thermotropic amphiphilic mesogens with hydrophilic groups at both terminals through the reaction of 2-hydroxyethylamine with omega-bromo-1-(4-(4-(2-hydroxyethyl)phenylazo)phenoxy)alkylamine. We examined the thermal and orientational properties of these mesogens. The mesogens formed fluid smectic phases due to interactions between the hydrophilic units. On heating a thermotropic amphiphilic mesogen (HE-6-OH) with a hexamethylene spacer chain, smectic A and C phases were formed. On cooling, HE-6-OH exhibited a smectic F phase and a G state in addition to smectic A and C phases. Further, the thermotropic amphiphilic mesogen with a dodecamethylene spacer chain showed smectic A and F phases on heating and cooling. (C) 2008 Elsevier B.V. All rights reserved.
Keywords:Liquid crystal;Hydrogen bond;Amphiphilic;Liquid crystalline orientation;X-ray;Thermal property