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Alan A. Jones1944-2006
Professor of Chemistry
Clark University
Worcester, MA
B.A., Colgate University, 1966
Ph.D., Chemistry, University of Wisconsin, 1972
Postdoctoral Fellow, Dartmouth College 1972-74
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Research and TeachingSynthetic polymers are often used as membranes in a wide variety of applications including separations, fuel cells and solid electrolytes. In these applications, the diffusion of small molecules or ions is of key importance. To follow translational motion, pulse field gradient nuclear magnetic resonance is used to determine the self-diffusion coefficient. Systems currently under investigation include high permeability polymers with a polyacetylene backbone and large side groups. Diffusion in these systems can be enhanced by up to an order of magnitude by the addition of nanoparticles and the mechanism for this enhancement is under investigation. Another way to prepare a polymer system with enhanced diffusion is to combine a high glass transition polymer with a low glass transition polymer in a blend. In this type of system the reorientational dynamics of both the polymer and the small molecule penetrants are followed by spin-lattice relaxation measurements and one and two dimensional solid state line shape exchange measurements. A Varian Inova 400 wide bore with full solids capability is used to conduct these NMR experiments.
Selected PublicationsGuoxing Lin and Alan A. Jones, “A Lattice Model for the Simulation of One and Two Dimensional 129Xe Line Shape Collapse by Translational Diffusion,” Solid State NMR 2004, 26, 87-98..
Jinghui Zhang 1, Marcus V. Giotto, Wen-Yang Wen, Alan A. Jones, “An NMR Study of the State of Ions and Diffusion in Perfluorosulfonate Ionomer,” Journal of Membrane Science, to appear..
Ernest Krygier, Guoxing Lin, Jessica Mendes, Gatambwa Mukandela, David Azar and Alan A. Jones, Jai A. Pathak , Ralph H. Colby Sanat K. Kumar , George Floudas , R. Krishnamoorti, “Segmental Dynamics of Head-to-Head Polypropylene and Polyisobutylene in their Blend and Pure Components,” Macromolecules, to appear..
Haihui Cao, Guoxing Lin, Alan A. Jones “Deuterium Solid Echo Line Shape Study of Poly(ethylene oxide) Dynamics in a Blend with Poly(methyl methacrylate),” Journal of Polymer Science, Polymer Physics Edition, to appear.
Junyan Zhong, Wen-Yang Wen and Alan A. Jones, “Translational and Rotational Motion of Cyclohexane in an Ultrapermeable Nanocomposite Membrane of Poly(2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole-co-tetrafluoroethylene) and Fumed Silica,” Macromolecules, to appear. | |