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 °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.

Graphical abstractThe lamellar and hexagonal liquid crystalline phases produced by new imidazolium ionic liquids lacking an acidic proton at the C-2 imidazolium ring position, in a 1-decanol-water solvent mixture.Figure optionsDownload full-size imageDownload high-quality image (71 K)Download as PowerPoint slide