摘要 |
Cationic or amphoteric (co)polymer obtained by Hofmann degradation reaction, in aqueous solution, in the presence of an alkaline-earth and/or alkali metal hydroxide and of an alkaline-earth and/or alkali metal hypohalide, on a base (co)polymer comprising at least one nonionic monomer chosen from the group comprising acrylamide (and/or methacrylamide) and N,N-dimethylacrylamide, is characterized in that the base (co)polymer is modified beforehand with at least one polyfunctional compound containing at least 3 heteroatoms chosen from N, S, O and P and each having at least one mobile hydrogen. Use as a flocculation, retention and/or drainage aid, and dry strength aid is contemplated.
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