ABSTRACT
A novel azoester series with chloro terminal group was synthesized and characterized for mesomorphic properties. It consists of 12 azoester derivatives from esterification reaction between 4-n-alkoxy-3-methoxy cinnamic acid and 4-hydroxy-2-methyl phenyl azo-4-chloro benzene. The isotropic temperature of homologous series LC compounds decreased with the increased of carbon in flexible chain. The present series is fully nematogenic and partially smectogenic in nature. The mesophase length is minimum 3.8 °C to maximum 64.3 °C. Mesophase property commences from first homologue of novel azoester series. Some mesogenic LC compounds were characterized by fourier-tranform infrared spectroscopy (FT-IR), Mass spectroscopy, proton nuclear magnetic resonance (1H-NMR) and elemental analysis. The mesogenic phases of novel azoester LC compounds confirm by polarized optical microscopy (POM) and their thermal properties of some homologue characterized by differential scanning calorimeter. Mesomorphic behaviours of novel azoester series are compared with structurally similar series.
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