Properties tuning of supramolecular discotics by non-mesogenic triazines and acids

Abstract

In this work, a new series of supramolecular discotic liquid crystals induced by hydrogen bonding between triazines T x and aromatic acids A y are presented, most of which exhibit columnar mesomorphic properties. The design strategy of combining the hydrogen bond parallel to the molecular plane with the π-stacking trend of triazine derivatives and aromatic acids was utilized, which has been widely confirmed by nematic, smectic or columnar liquid crystal phases. The formation of hydrogen bonded complexes was proven by FT-IR and 1H NMR spectroscopy and their stability studied by variable temperature FT-IR techniques. All prepared hydrogen bonded complexes displayed mesogenic properties and their liquid crystalline properties were investigated by means of DSC, POM and XRD. This work provides useful information to assist our further design of hydrogen bonded supramolecular liquid crystals for optoelectronic applications.