LOW MOLAR MASS LIQUID-CRYSTALLINE GLASSES - PREPARATION AND PROPERTIES OF THE ALPHA-(4-CYANOBIPHENYL-4'-OXY)-OMEGA-(1-PYRENIMINEBENZYLIDENE-4'-OXY)ALKANES

Ten members of the asymmetric dimer homologous series alpha-(4-cyanobiphenyl-4'-oxy)-omega-(1-pyren-iminebenzylidene-4'-oxy)alkanes have been synthesized, and their mesogenic properties characterized. All the homologues exhibit glassy behavior, forming either nematic or smectic glasses, above room temperature. The thermal behavior of this series is discussed in detail, and the transitional properties of the homologues are compared to those of the related alpha,omega-bis(1-pyreniminebenzylidene-4'-oxy)alkanes and alpha,omega-bis(4-cyanobiphenyl-4'-oxy)alkanes dimer series. The differences between these series are interpreted in terms of changes in the anisometry of the molecular shape. The application potential of these novel materials is discussed briefly.