Mixed Micelle of Surface Active Ionic Liquid Lauryl Isoquinolinium Bromide and Nonionic Surfactant Triton X-100 in Aqueous Solutions

The critical micelle concentrations of binary systems of surface active ionic liquid lauryl isoquinolium bromide ([C(12)iQuin]Br) with nonionic surfactant Triton X-100 in aqueous solution were investigated by isothermal titration calorimetry. The location of [C(12)iQuin]Br and Triton X-100 in the mixed micelle was studied using 'H nuclear magnetic resonance (NMR) and two-dimensional nuclear Overhauser enhancement spectroscopy (2D NOESY). It was found that the polyoxyethylene chain of Triton X-100 forms random coils around the isoquinolinium ring. The interaction of molecules in the mixed micelle of [C12iQuin]BrTriton X-100 was also studied using regular solution theory and the cloud point measurement technique, with comparison to the interaction of doceyl trimethyl ammonium bromide (DTAB)-Triton X-100.