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Title
Accessibility and supermolecular structure of cellulose
Authors
Michael Ioelovich and Alex Leykin
Received
October 10, 2009
Published
Volume 43 Issue 9-10 October-December
Keywords
cellulose, structure, accessibility, crystallinity, reactivity
Abstract
The accessibility of cellulose samples with various crystallinity degrees to molecules of water, lower primary alcohols and lower organic acids was studied. It was found out that small water molecules have full access to the non-crystalline domains of cellulose (accessibility coefficient ? = 1). The molecules of the lowest polar organic liquids have partial access to these domains (? < 1), while, with an increasing diameter of the organic molecules, their access to the cellulose structure decreases. The accessibility of cellulose samples to molecules of various substances is a linear function of coefficient ? and of the content of non- crystalline domains. The relationship between the crystallinity (X) and accessibility (A) of cellulose to the molecules of some liquids was established as A = ? (1-X). The water molecules were found to have greater access to the cellulose samples than the molecules of the investigated organic liquids. The obtained results permit the use of accessibility coefficient values to estimate cellulose crystallinity, to examine the structural state of the non-crystalline domains and to predict the reactivity of cellulose samples towards some reagents.
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