Phase characterization of two homologous series of LC methacrylic monomers based on omega-hexyl- and omega-butyl-oxysalicylaldimine groups with different alkoxy tail substitutions

Abstract

The phase characterization of two homologous series of liquid crystalline methacrylic monomers based on omega-hexyl- and omega-butyloxysalicylaldimine groups, with different alkoxy tails, is presented. The liquid crystalline materials were characterized by polarising optical microscopy. differential scanning calorimetry, differential thermal analysis, and X-ray diffraction. All the monomers exhibit the simultaneous occurrence of smectic A and C phases, When the alkyl chain is short narrow nematic phase is observed, leading to an I-N-SmA-SmC phase sequence.