Abstract:
The lamellar lyotropic liquid crystal was formed in [C12mim]Br/SDS mixed aqueous solutions under certain condition as observed in our experiments. As temperature decreased, lamellar liquid crystal phase translated to a new type of spiral liquid crystal, whose chirality was analyzed by circular dichroism (CD). Imidazolium based ionic liquid plays a leading role during this transition. Non covalent bonding interactions between the molecules including hydrogen bond network, π π stacking interaction, the hydrophobic interaction among surfactants, and the strong electrostatic attractive interaction of opposite charged polar head are the main driving force of the formation of liquid crystal. Because of the weakened molecular thermal motion, hydrogen bond network and π π stacking interaction formed and kept stable at low temperatures, which led to the formation of spiral liquid crystal.