Enhancement of thermal, dielectric and electro-optical properties of fluoro hydrogen-bonded liquid crystals

ABSTRACT

The present work reported the synthesis and the characterisation of laterally fluorinated handed bond liquid crystals (HBLCs) prepared by intermolecular hydrogen bonds between 4-pentyl-4-biphenylcarbonitrile (5CB) and 4-(nonyloxy)-3-fluoro benzoic acid (9OBAF). This compound-denoted 9OBAF-5CB was characterised by Fourier transform infrared spectroscopy (FTIR) and their mesomorphic properties were studied by polarising optical microscope (POM) and differential scanning calorimetry (DSC). Moreover, this compound shows a wide nematic phase with relatively high birefringence ($\left(\mathrm{\Delta }n=0.24\right)$, modest dielectric anisotropy $\left(\mathrm{\Delta }\epsilon =5\right)$, low viscosity (γ = 182.9 mPas). The enhancement of these parameters compared to that in individual compounds (9OBAF) and 5CB was obtained and discussed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Hydrogen-bonded liquid crystal
• nematic
• dielectric anisotropy
• electro-optical
• viscoelastic properties

Disclosure statement

No, potential conflict of interest was reported by the author(s).