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A New Straightforward Method for Lipophilicity (logP) Measurement using 19F NMR Spectroscopy
Published on: January 30, 2019
Water partitioning in "dry" poly(ethylene oxide) alcohol (CmEn) nonionic surfactant--a proton NMR study
Markus M Hoffmann1, Megan E Bennett, Jack D Fox
1Department of Chemistry, State University of New York College, Brockport, NY 14420, USA. mhoffman@brockport.edu
Abstract:
A proton NMR titration study is presented where in small increments quantities of water were added to "dry" CmEn nonionic surfactant. For a particular range of compositions, two resonances for the water/hydroxyl protons were observed that display large chemical shift increases as water content is increased indicating that water must partition between two chemical environments with a surprisingly slow chemical exchange rate. A detailed mechanism of how the increasing amounts of water are incorporated into the surfactant medium is presented accounting for all observed spectral changes.
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