B. Ellis, M. P. Mcdonald
Feb 1, 1969
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Influential Citations
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Journal
Journal of Non-crystalline Solids
Abstract
Abstract N.M.R. line width and second moment measurements have been made on α-D glucose penta-acetate (α-D G.P.A.) in the crystalline and glassy states between 120 and 390°K. The glass transition temperature, T g = 285 – 7°K, was determined by thermal analysis, and above this temperature there is rapid N.M.R. line narrowing due to molecular motion which is sufficient for facile crystallisation to occur. The second moments at low temperatures of glassy and crystalline α-D G.P.A. are identical within experimental error and show that methyl group rotation still occurs at 120°K, but for glassy α-D G.P.A., there is an indication of further molecular motion 50°K below T g .