Journal of Thermal Analysis and Calorimetry

, Volume 132, Issue 2, pp 989–1000 | Cite as

Self-assembled liquid crystalline materials with fatty acids

FTIR, POM and thermal studies
  • Sangeetha G. Bhat
  • Girish Sharada Ramachandra
  • Poornima Bhagavath
  • Mahabaleshwara Subrao
  • D. M. Potukuchi
  • Srinivasulu Maddasani


Two new series of liquid crystalline materials with non-mesomorphic fatty acids, viz. nonanoic (C9), capric (C10), undecanoic (C11), tridecanoic (C13), myristic (C14), palmitic (C16) and stearic acids (C18), are prepared with non-mesomorphic proton acceptors, viz. (4-pyridyl)-benzylidene-p-n-alkylanilines (PyBnA; n = 12 and 16). The smectic phase structures formed between the proton donor (fatty acid) and proton acceptor moieties are found due to the intermolecular hydrogen bonding (HB) and are monotropic. The presence of HB is confirmed by Fourier transform infrared spectroscopy in all the compounds. The characteristic optical textures of smectic phases are observed through polarizing optical microscope, provided with a hot stage and a camera. The phase transition temperatures and the enthalpy changes across the phase transitions are determined by differential scanning calorimetry. The smectic phase exhibited by the HB complexes is confirmed by miscibility studies as smectic-B. The ππ stacking interactions in layers are found to influence the mesomorphism in these HB complexes.


Fatty acids Pyridyl moieties Hydrogen bonding Smectic-B phase Miscibility studies FTIR studies Polarizing optical microscope Thermal studies 



The authors are grateful to the management of Manipal University for infrastructural facilities. Also the partial financial support by Innovation Centre, Manipal University, is acknowledged.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.Department of Chemistry, Manipal Institute of TechnologyManipal UniversityManipalIndia
  2. 2.Department of Physics, University College of EngineeringJawaharlal Nehru Technological University: KakinadaKakinadaIndia

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