Systematic studies on eight homologous series of supramolecular hydrogen bonded liquid crystals

Abstract

Design, synthesis and characterization of hydrogen bonded liquid crystals (HBLC) formed by alkyloxy benzoic acids (referred as nOBA : ABOm) are discussed. Eight such homologous series of HBLC are synthesized with varying the carbon chain length from 5 to 12 referred as nOBA : ABOm. These complexes are characterized by polarizing optical microscope (POM), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) studies. Phase diagrams of the individual series have been constructed from the data of POM and DSC respectively. The effect of the chain length on the phase formation is discussed. Thermodynamic evaluation of nOBA : ABOm homologues series has been carried out. It is observed that the entire eight homologous series possess thermodynamically equilibrium energy states. The results of phase variance influence of chain length, phase transitions and corresponding enthalpy values are discussed.

Keywords:

• alkyloxy benzoic acids
• polarizing optical microscope
• phase variance
• thermodynamic equilibrium
• enthalpy values

Acknowledgements

The authors acknowledge the infrastructural support provided by Bannari Amman Institute of Technology, Sathyamangalam, India and divine blessings of Almighty Bannari Amman.