Hydrogen Bonded Supramolecular Liquid Crystalline Complex of 2,4,6‐Triarylamino‐1,3,5‐triazines with Semiperfluorinated Benzoic Acids

Abstract

AbstractHydrogen bonded supramolecular complexes of 2,4,6‐triarylamino‐1,3,5‐triazines (Tn) with semiperfluorinated benzoic acids have been prepared. The mesophase behaviors of such complexes were investigated with POM (polarized optical microscopy), DSC (differential scanning calorimetry) and X‐ray diffraction. Columnar mesophase was found in the equimolar mixtures of the triazines with the semiperfluorinated benzoic acids. While the equimolar mixture of triazines with the nonfluorinated three fold alkoxy‐modified carboxylic acid was not mesogen. The mesophase formation is analyzed as the hydrogen bonding between the Tn and benzoic acid which leads to discrete dimeric supermolecule and enhances the polarity of the core region of the dimeric supermolecule; simultaneously, an increased intramolecular polarity contrast upon replacing alkyl chains by semiperfluorinated chains, which favors a microsegregation, and leads to the fromation of the columnar phase.