The effect of fluorocarbon tails on the phase behaviour of some Schiff's base liquid crystals

Several new liquid crystalline compounds comprising Schiff's-base cinnamate cores and fluorocarbon alkoxy tails of varying lengths have been synthesized and characterized. The thermal properties of these materials are compared to those of their hydrocarbon analogues. The results show that fluorination stabilizes the crystalline phase, quite unexpectedly destabilizes the S_c phase, and for two of the compounds produces extraordinarily stable S_A phases.