Shaping 1,2,4-Triazolium Fluorinated Ionic Liquid Crystals

The synthesis and thermotropic behaviour of some di-alkyloxy-phenyl-1,2,4-triazolium trifluoromethane-sulfonate salts bearing a seven-carbon atom perfluoroalkyl chain on the cation is herein described. The fluorinated salts presenting a 1,2,4-triazole as a core and differing in the length of two alkyloxy chains on the phenyl ring demonstrated a typical liquid crystalline behaviour. The mesomorphic properties of this set of salts were studied by differential scanning calorimetry and polarized optical microscopy. The thermotropic properties are discussed on the grounds of the tuneable structures of the salts. The results showed the existence of a monotropic, columnar, liquid crystalline phase for the salts tested. An increase in the temperature mesophase range and the presence of two enantiotropic mesophases for the sixteen-atom alkyloxy chain salt can be observed by increasing the length of the alkyloxy chain on the phenyl ring.

Automated summary

The synthesis and thermotropic behavior of certain di-alkyloxy-phenyl-1,2,4-triazolium trifluoromethanesulfonate salts with a seven-carbon atom perfluoroalkyl chain on the cation were investigated. The fluorinated salts exhibited typical liquid crystalline behavior, with a 1,2,4-triazole core and varying lengths of alkyl chains on the phenyl ring. The mesomorphic properties of these salts were studied using differential scanning calorimetry and polarized optical microscopy. The results showed the presence of a monotropic, columnar, liquid crystalline phase in the tested salts, with an increased temperature mesophase range and the presence of two enantiotropic mesophases observed with the increase in alkyl chain length on the phenyl ring.