Examining the influence of molar ratio variation over the phase variance observed in hydrogen bond liquid crystal binary mixtures formed between benzoic acids and 4-Nitrobenzaldehyde

Four binary mixtures are isolated from two hydrogen bond mesogenic complexes that are formed between p-n alkyloxy benzoic acids and 4-Nitrobenzaldehyde. The carbon chain length chosen for the formation of binary mixtures are heptyloxy and octyloxy benzoic acids. 4-Nitrobenzaldehyde (NBA) and heptyloxy benzoic acid mesogenic complex is treated as X component while 4-Nitrobenzaldehyde (NBA) and octyloxy benzoic acid mesogenic complex is treated as Y component. Binary mixtures are obtained by varying the molar ratio of the two mesogenic complexes ( X and Y ) in even steps viz., from 0.2 to 0.8. Hydrogen bond existence between the binary mixtures is confirmed through Fourier Transform Infrared Spectroscopy. Mesogenic phase variance is investigated through polarizing optical microscope study. The phase transition temperature and their corresponding enthalpy values are analyzed via differential scanning calorimetry. Thermal equilibrium, thermal stability, order of phase transition and specific heat capacity of the binary mixtures are also elucidated from the thermograms of the mesogenic mixtures. The results obtained make these binary mixtures a potential candidate for opto-electronic and thermal energy based applications.