HYDROGEN-BONDING AND THE SELF-ASSEMBLY OF SUPRAMOLECULAR LIQUID-CRYSTALLINE MATERIALS

Novel supramolecular liquid-crystalline materials have been obtained by the hydrogen bond formation between different and independent molecules. The self-assembly of carboxylic acid and pyridine moieties that function as H-bond donors and accepters, respectively, results in the formation of mesogenic complex structures. A wide variety of liquid-crystalline low molecular weight complexes have been prepared using this approach. This concept has been extended to the polymeric systems. Hydrogen-bonded liquid-crystalline polymers that exhibit mesophases over wide temperature ranges, ferroelectricity or photo-responsibility have been prepared by the molecular association. Moreover, Liquid-crystalline polymer networks that show reversible smectic-isotropic phase transitions have been formed by the hydrogen bonds. The dynamics of the hydrogen bonding may contribute to the induction of the mesomorphism of the networks.