Synthesis and Some Physical Properties of 1-Cyclohexyl-phenyl-2-Methyl Ethylenes

Abstract

A series of trans-1-{4′-(trans-4”-n-alkylcyclohexyl)phenyl}-2-methylethylenes, which show nematic phases, were prepared. Their transition temperatures, enthalpies and entropies were measured. The phase diagrams for their binary mixtures were made and the birefringences and flow-aligned viscosities were measured. Five nematic mixtures were prepared to compare the properties of the ethylenes with those of other cyclohexylbenzenes having other terminal groups. The 1-cyclohexyl-phenyl-2-methylethylenes have wide nematic ranges with high N-I transition temperatures and high birefringences. Their photochemical stabilities were tested.

Keywords:

• liquid crystal
• cyclohexane
• ethylene
• hydrocarbon