Chinese Journal of Magnetic Resonance (Mar 2018)
An NMR Study on Two Mixed Micelles Formed by Nonionic Surfactants
Abstract
NMR techniques were used to study the relative arrangement and interaction sites in mixed micelles formed in NP-10/Tween40 and NP-10/C10E6 aqueous solutions. The results of two-dimensional NOESY experiments and relaxation time measurements showed that the interaction site of these two pairs of mixed surfactants were similar, but the intermolecular interaction between NP-10 and Tween40 was stronger than that between NP-10 and C10E6. T2 measurements demonstrated that inter-heteromolecular interactions decreased when the molar concentrations of Tween40 and C10E6 were larger than 2 and 4 folds of that of NP-10, respectively. Under such circumstances, the inter-homomolecular interactions began to play a key role, indicative of the ideal mixture molar ratio and the change of synergistic effect in the complex systems. T2/T1 ratio measurements indicated that molecular chain movement in the NP-10/Tween40 mixture was more limited than that in the NP-10/C10E6 mixture. The above conclusions were verified by spatial distance measurements.
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