Novel comb polymers which can be used in cosmetics and detergents

A water-soluble copolymer comprising, by mass relative to the total mass of the copolymer, units derived from:

• 1 to 40% of at least one cationic monomer whose cationicity comes exclusively from one or more quaternary ammonium functional groups;
• 59.99 to 98% of at least one nonionic monomer;
• 0.01 to 10% of at least one monomer of formula (I);
• in which:
• R1 is a hydrogen atom or a methyl radical;
• Z is a functional group chosen from the group consisting of a covalent bond, an oxygen atom, the divalent group —CH2—O—, —C(═O)—O—, and —(═O)—NH—;
• n is an integer between 2 and 200;
• R2 is a hydrogen atom or a carbon-containing radical which is saturated or unsaturated, optionally aromatic, linear, branched or cyclic, comprising 1 to 30 carbon atoms, and from 0 to 4 heteroatoms chosen from the group consisting of O, N and S;
• the copolymer having a cationic charge density between 0.05 and 3 meq/g.