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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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Esterification of hydroxyethyl cellulose with p-nitrobenzoyl chloride at the phase interface
M. Pašteka and F. Brauer
Institute of Chemistry, Slovak Academy of Sciences,
Bratislava
Abstract: Low level substituted hydroxyethyl cellulose when acylated with ^-nitrobenzoyl
chloride in the boundary between phases led to a derivative of esterification degree 1.5
which is one half of the feasible value. However, the acyl substituents are not regularly
alternated on the hydroxyl groups C6, or C2 and C3 of the neighbouring glucose unit of
the cellulose derivative macromolecule, as anticipated on the basis of the assumption
of particular orientation of the cellulose macromolecules toward the boundary of phases
in the moment of reaction.
The extraction of the thus formed p-nitrobenzoylhydroxyethyl cellulose with acetone,
eventually its fractional precipitation with methanol from its dimethylformamide
solution showed that there is a series of different esterified, even though unesterified
glucose units present in the macromolecules of cellulose after the reaction. The irregularity
in distribution of acyls in the cellulose macromolecules is explained by the fact that the
macromolecules are not rigid and that their character, as well as their colloidochemical
properties undergo changes in the acylation reaction course.
Full paper in Portable Document Format: 228a610.pdf (in Slovak)
Chemical Papers 22 (8) 610–614 (1968)
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