NOVEL METHOD FOR PREPARING ACRYLAMIDE COPOLYMERS BY HOFMANN DEGRADATION REACTION

摘要

The invention relates to a method for preparing cationic or amphoteric (co)polymers derived from acrylamide by a Hofmann degradation reaction in an aqueous solution in the presence of an alkaline and/or alkaline-earth hydroxide and of an alkaline hypohalide on a base copolymer characterised in that the base solution on which the reaction is carried out contains a polyvalent cationic salt representing at least 0.5 wt % and preferably 2 to 10 wt % of the base copolymer.