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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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Sulfation of cross-linked polysaccharides by the N,N-dimethylformamide-SO3 complex
M. Kučerová and M. Pašteka
Institute of Chemistry, Slovak Academy of Sciences,
809 33 Bratislava
Abstract: The reactivity of cross-linked starch and microcrystalline cellulose at
sulfation is reduced by their preliminary drying which is accompanied by
formation of secondary intermolecular bonds. Due to its preswelling effect,
dry N,N-dimethylformamide destroys partially the intermolecular bonds
thus facilitating the preparation of sulfated derivatives.
Sodium salts of sulfated cross-linked polysaccharides are stable in the air
as well as in water. However, in an H form they submit to autohydrolysis
with a subsequent loss of weight and deterioration of their colloid properties.
Regarding the above-mentioned fact, the possibility of an application of
sulfated cross-linked polysaccharides as ion exchangers seems to be limited.
Full paper in Portable Document Format: 295a697.pdf
Chemical Papers 29 (5) 697–702 (1975)
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