SYNTHESIS OF HIGH-TEMPERATURE MESOMORPHIC POLYSILOXANES AND THEIR USE AS STATIONARY PHASES FOR HIGH-RESOLUTION GAS-CHROMATOGRAPHY

Abstract

Two new liquid crystalline polysiloxanes with very wide mesomorphic temperature range have been prepared. One containing 4-[(S)-2-methyl-1-butoxy]phenyl 4-hexanyloxy-biphenyl-4'-carboxylate side groups displays enantiotropic smectic A, chiral smectic C and smectic B phases. The other containing (S)-2-methyl-1-butyl 6-(4-undecanyloxybiphenyl-4'-carbonyloxy)-2-naphthalenecarboxylate side groups exhibits only an enantiotropic cholesteric phase. Both mesomorphic polysiloxanes were used as stationary phases in gas chromatography capillary columns. They show very unique separating properties for various isomeric halogenated naphthalene compounds, methylanthracene compounds, fatty acid methyl esters and polycyclic aromatic compounds.