Study of thermal and electrical properties exhibited by two ferroelectric self assembly systems

Two series of inter hydrogen bonded ferroelectric liquid crystals have been isolated. In one of the series hydrogen bond is formed between p-n-alkyloxy benzoic acids and (S)-1,2-cholo-3-(4-hydroxy) phenyl propionic acid (CTy + nOBA) while in the other it is formed between p-n-alkyl benzoic acids and (S)-1,2-cholo-3-(4-hydroxy) phenyl propionic acid (CTy + nBA). Detailed synthetic route for the isolation of these compounds is discussed. Formation of the ferroelectric self assembly systems has been evinced through FTIR studies. The positional influence of oxygen atom is investigated from the thermal and electrical characterization of both the series. Polarizing optical microscope (POM) studies on CTy + nBA hydrogen bonded complexes reveals that they exhibit single phase variance while the other complex CTy + nOBA exhibit rich phase polymorphism. It is observed that the presence of oxygen atom enhances phase abundance. Phase diagrams for both the complexes are constructed from the DSC and POM studies. Dielectric relaxations and activation energies have been carried out for various phases in CTy + 8OBA and CTy + 8BA complexes. It has been observed that the oxygen atom originates type I relaxation process. Two molecular modeling have been assigned to account for the dielectric relaxation process observed in both the HBFLC series.