Process for the preparation and workup of aqueous medium-soluble N-hydroxyalkyl chitosans

摘要

The present invention relates to a process for the preparation and workup of N-hydroxyalkylchitosans which are soluble in aqueous medium, comprising the measures of dispersion of chitosan in an aqueous medium, subsequent hydroxyalkylation of the dispersed chitosan and subsequent workup of the N-hydroxyalkylchitosan, which is characterised in that the hydroxyalkylation is carried out up to an average degree of substitution (DS) of 2.0, preferably 1.5 to 2.0, after the hydroxyalkylation and before the workup a part of the aqueous medium is removed where appropriate, and the workup of the N-hydroxyalkylchitosan takes place by drying.