Patent ID: 8492495

Claim:
A salified copolymer obtained by salification, in an aqueous medium, using at least one amine containing at least one nitrogenous heterocyclic group, of a copolymer obtained from at least one cyclic anhydride-based or carboxylic acid-based monomer and from at least one styrene-based monomer, wherein the amine corresponds to any one of the following formulae (1) to (6): where A denotes an oxygen or sulphur atom or an NH group, X denotes a linear or branched C 1 -C 10 alkylene chain, optionally interrupted with one or more nitrogen atoms, and terminated with a primary or secondary amine function, and Y and R each denote any chain terminated with a primary or secondary amine function, and wherein the salified copolymer comprises nitrogen heterocycles derived from the amine linked to the backbone of the copolymer by ionic bonds.