MESOMORPHIC PROPERTIES OF NOVEL LIQUID-CRYSTALS WITH TETRAFLUOROBIPHENYLENE

Properties of ferroelectric mesomorphic phases were investigated by pl otting hysteresis loops of spontaneous polarization versus electric he ld with sinusoidal waveform for 4'-[(s)2-methylbutoxycarbonyl] phenyl y-2,3,5,6-tetrafluorobiphenyl-1-ethynyl)benzoates. The compounds show enantiotropic mesophases of cholesteric, smectic A and chiral smectic C states in a rather wide temperature range. The ferroelectric mesopha se has the maximum range of 108 degrees C, a polarization of above 10( -5) C/m(2) and a melting point near 61 degrees C in one material with a alkoxy group possessing the length of nine carbons.