Use of NMR Imaging to Determine the Diffusion Coefficient of Water in Bio-based Hydrogels

Authors: Doll, Kenneth - Ken

Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: 11/16/2009
Publication Date: 5/19/2010
Citation: Doll, K.M. 2010. Use of NMR Imaging to Determine the Diffusion Coefficient of Water in Bio-based Hydrogels [abstract]. Annual Meeting and Expo of the American Oil Chemists' Society. p. 9.

Interpretive Summary:

Technical Abstract: The diffusion of liquid in a hydrogel material is a fundamental property which must be controlled in order to create effective delivery systems for the agricultural and pharmaceutical industries. NMR spectroscopy has been used to determine the diffusion of water and deuterium oxide in a bio-based hydrogel system. Utilizing an imaging experiment and normalizing and fitting the data to a mathematical treatment published by J. Crank, a diffusion constant of 6.267 x 10-10 m2s-1 was uncovered in a well known biobased water absorbing system. This is considerably slower than the value of for free water, 2.4 x 10-9 m2s-1, showing that the release of solutes from this would be appropriate for some applications. A less quantitative experiment utilizing a dye solution shows a similar trend. These experiments give another parameter which must be optimized to help create high value products from agricultural materials.