Characterization of a Reverse Hexagonal Lyomesophase by a PGSE

Pulsed field gradient spin-echo (PGSE) FT-NMR experiments have been performed in order to ... study water self-diffusion in the reverse hexagonal phas...
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4180

Langmuir 2000, 16, 4180-4184

Characterization of a Reverse Hexagonal Lyomesophase by a PGSE NMR Water Self-Diffusion Study L. Coppola,* C. Oliviero, U. Olsson,† and G. A. Ranieri Department of Chemistry, University of Calabria, 87030 Arcavacata di Rende (CS), Italy Received November 8, 1999. In Final Form: January 20, 2000 Pulsed field gradient spin-echo (PGSE) FT-NMR experiments have been performed in order to characterize the structure of a reverse hexagonal lyomesophase of a nonionic surfactant-water-oil system, weakly charged. The nonionic surfactant system contains pentaethylene glycol dodecyl ether (C12E5), water, decane, and small amounts of an ionic surfactant, sodium dodecyl sulfate (SDS). The observed spin-echo attenuation due to water self-diffusion at different temperatures and compositions has been interpreted with a one-dimensional diffusion model, i.e., a self-diffusion in randomly oriented array of capillaries with both transverse dimensions