Synthesis and Physical Properties of Novel Dimesogenic Compounds Possessing both Lateral and Terminal Polar Groups.

We prepared a homologous series of non-symmetric dimesogenic compounds 1-(4- fluorophenyl)-4-{ω -{4-[4-(4-hexylphenyl)-2,3-difluorophenyl]phenyloxy}alkyloxy} benzene (I-n) and investigated the physical properties. For comparison, we also prepared a compound (II-6) possessing a 4-(4-cyanophenyl)benzene unit instead of the 4-(4- fluorophenyl)benzene unit. All the compounds exhibited an enantiotropic nematic phase. When an electric AC field was applied, a striped pattern that was similar to Williams domain appeared in the nematic phases of compounds I-n, whereas such a pattern was not observed in the nematic phase of II-6. We discuss structure-property correlations of the polar liquid crystal oligomers. [ABSTRACT FROM AUTHOR]