Investigations on thermotropic hydrogen bond liquid crystals

Abstract

Novel hydrogen bond liquid crystal homologous series derived from alkyloxy benzoic acids and α-ketoglutaric acid are isolated and experimented. This homologous series referred as KGA + nBAO comprises of eight mesogens in which the alkyloxy benzoic acid varied from pentyloxy to dodecyloxy. Fourier Transform Infrared Spectroscopy analysis confirmed the formation of hydrogen bond. Optical polarizing microscopy reveals that this homologous series exhibits three phases namely nematic, smectic C and smectic G. The transition temperatures obtained by Differential Scanning Calorimetry and optical microscopy and corresponding enthalpy values are tabulated for all the homologues of the series and various thermal parameters are derived.

Keywords:

• Hydrogen bond
• liquid crystal
• α-ketoglutaric acid
• DSC
• FTIR

Acknowledgments

The authors acknowledge the infrastructural facilities provided by Bannari Amman Institute of Technology, Sathyamangalam.

Disclosure statement

No potential conflict of interest was reported by the authors.