METHOD OF PRODUCING N,S-CONTAINING, CHITOSAN-BASED POLYMER Russian patent published in 2013 - IPC C08B37/08 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of producing a N,S-cyclo-containing chitosan derivative. Described is a method of producing a chitosan-based N,S-cyclo-containing polymer (I) which contains in the macrochain 1-oxa-6-thia-4,8-diazocycloundecane fragments: I, by reacting chitosan with formaldehyde and a S-containing compound, characterised by that the S-containing compound used is hydrogen sulphide, the formaldehyde solution is pre-saturated with H₂S and the reaction is carried out with molar ratio chitosan: formaldehyde: hydrogen sulphide of 1:2:1, at temperature of 0-60°C in a chloride medium for 24 hours.

EFFECT: obtaining modified chitosan which exhibits properties of a highly efficient heavy metal sorbent for waste water treatment, an extractant for separating rare, noble and precious metals and a complexing agent for biological molecules.

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