Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 7-Day Trial for You or Your Team.

Learn More →

Solid State NMR Studies on Cellulose Crystallinity in Fines and Bulk Fibres Separated from Refined Kraft Pulp

Solid State NMR Studies on Cellulose Crystallinity in Fines and Bulk Fibres Separated from... Summary Solid state NMR spectroscopy has been used in this work to investigate crystallinity of cellulose in spruce wood before and after kraft pulping and TCF bleaching. Effects of refining of the spruce kraft pulp in water and in weak alkali have been studied by determination of the crystallinity of isolated fines and corresponding bulk fibres in order to find out whether the crystallinity in the fibre surface material and inside the fibre wall differ from each other. Also the possible effect of enzymatic endo-1,4-β-galactanase treatment on the crystallinity of some refined pulps has been investigated. It was found that the I α crystalline form of cellulose predominates over the I β form in native spruce and vice versa in all the pulps studied. In pulping part of the cellulose I α is converted to the more stable I β form mainly by heat. Any measurable changes in the degree of crystallinity or in the relative proportions of different crystalline forms of cellulose could not be seen in pulps after refining, TCF-bleaching or galactanase treatment. However, the degree of crystallinity was found to be considerably lower in the fines compared to the corresponding bulk fibres. Therefore it is suggested that the cellulose crystallinity is lower or the size of crystallites smaller on the fibre surface than inside the fibre wall. Slightly higher contents of lignin and hemicelluloses, mainly xylan and mannan, were also found in the fines compared to the bulk fibres. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Holzforschung de Gruyter

Solid State NMR Studies on Cellulose Crystallinity in Fines and Bulk Fibres Separated from Refined Kraft Pulp

Liitiä, T.; Maunu, S. L.; Hortling, B.
Holzforschung , Volume 54 (6) – Oct 25, 2000
Download PDF
7 pages

Loading next page...
 
/lp/de-gruyter/solid-state-nmr-studies-on-cellulose-crystallinity-in-fines-and-bulk-IPgwLKFJFm

References (36)

Publisher
de Gruyter
Copyright
Copyright © 2000 by the
ISSN
0018-3830
DOI
10.1515/HF.2000.104
Publisher site
See Article on Publisher Site

Abstract

Summary Solid state NMR spectroscopy has been used in this work to investigate crystallinity of cellulose in spruce wood before and after kraft pulping and TCF bleaching. Effects of refining of the spruce kraft pulp in water and in weak alkali have been studied by determination of the crystallinity of isolated fines and corresponding bulk fibres in order to find out whether the crystallinity in the fibre surface material and inside the fibre wall differ from each other. Also the possible effect of enzymatic endo-1,4-β-galactanase treatment on the crystallinity of some refined pulps has been investigated. It was found that the I α crystalline form of cellulose predominates over the I β form in native spruce and vice versa in all the pulps studied. In pulping part of the cellulose I α is converted to the more stable I β form mainly by heat. Any measurable changes in the degree of crystallinity or in the relative proportions of different crystalline forms of cellulose could not be seen in pulps after refining, TCF-bleaching or galactanase treatment. However, the degree of crystallinity was found to be considerably lower in the fines compared to the corresponding bulk fibres. Therefore it is suggested that the cellulose crystallinity is lower or the size of crystallites smaller on the fibre surface than inside the fibre wall. Slightly higher contents of lignin and hemicelluloses, mainly xylan and mannan, were also found in the fines compared to the bulk fibres.

Journal

Holzforschung – de Gruyter

Published: Oct 25, 2000

There are no references for this article.