A NOESY NMR-STUDY OF THE INTERACTION BETWEEN SODIUM DODECYL-SULFATE AND POLY(ETHYLENE OXIDE)

The system poly(ethylene oxide) (PEG) and sodium dodecyl sulfate (SDS) will in aqueous solution form SDS micelle-like aggregates on the poly mer when a critical surfactant concentration (c.a.c.) is reached. The two-dimensional nuclear Overhauser enhancement NMR (NOESY) experiment capable of revealing spatial relationships among proximal protons has been applied to the PEO/SDS system to study structural details of thei r interaction. NOESY cross-peaks at sample temperatures of 283.1 and 2 98.1 K indicate proximity (<5 Angstrom) of the polymer protons and the main part of the surfactant hydrocarbon chain. The results indicate t hat the polymer (PEG) penetrates into the interior of the SDS micelles . (C) 1996 Academic Press, Inc.