Self-assembly of lyotropic liquid crystal phases in ternary systems of 1,2-dimethyl-3-hexadecylimidazolium bromide/1-decanol/water

Ternary mixtures of 1,2-dimethyl-3-hexadecylimidazolium bromide/1-decanol/water form two types of well-ordered lyotropic ionic liquid crystals, a hexagonal phase linked to the ionic liquid-water axis, and a lamellar phase located at the center of their phase diagram. The lamellar and hexagonal phases span a wide temperature range from 3 to 40 degrees C, depending on the composition. The spontaneous self-assembly of the mixtures arises from strong association between the hydroxyl groups of 1-decanol or water and the polar head-groups of the ionic liquid (head-group solvent), aromatic stacking interaction between the imidazolium rings and the hydrophobic effect. (C) 2009 Elsevier Inc. All rights reserved.