Comb polymers which can be used in cosmetics and detergents

1. A water-soluble copolymer comprising, by mass relative to the total mass of the copolymer:

5 to 45% of at least one cationic monomer whose cationicity comes exclusively from one or more quaternary ammonium functional groups;

50 to 95% of at least one monomer of formula (I);

in which:

R 1 is a hydrogen atom or a methyl radical;

Z is a divalent group —C(═O)—O—, or —C(═O)—NH—;

n is an integer that is 2 to 200;

R 2 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 of between 0.3 and 2.6 meq/g,

wherein the copolymer also comprises at least one nonionic monomer distinct from the monomer of formula (I).

2. The copolymer according to claim 1 , wherein the copolymer has a cationic charge density of between 0.5 and 1.5 meq/g.

3. The copolymer according to claim 1 , wherein the monomer of formula (I) is chosen from the group consisting of:

poly(ethylene glycol)(meth)acrylate in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =H; n=2 to 200;

methyl-poly(ethylene glycol)(meth)acrylate, also called methoxy-poly(ethylene glycol)(meth)acrylate, in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =CH 3 ; n=2 to 200;

alkyl-poly(ethylene glycol)(meth)acrylates in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =C 1 -C 30 alkyl; n=2 to 200; and

phenyl-poly(ethylene glycol)(meth)acrylates, also called poly(ethylene glycol)phenyl ether(meth)acrylate, in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =phenyl; n=2 to 200.

4. The copolymer according to claim 3 , wherein the monomer of formula (I) is chosen from the group consisting of poly(ethylene glycol)(meth)acrylates and methyl-poly(ethylene glycol)(meth)acrylates, having a molar mass of between 80 and 8000 g/mol.

5. The copolymer according to claim 1 , wherein the cationic monomer is chosen from the group consisting of quaternized dimethylaminoethyl acrylate (ADAME), quaternized dimethylaminoethyl methacrylate (MADAME), dimethyldiallyl ammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (APTAC) and methacrylamidopropyltrimethylammonium chloride (MAPTAC).

6. The copolymer according to claim 1 , wherein the nonionic monomer distinct from the monomer of formula (I) represents less than 25% by mass of the copolymer.

7. The copolymer according to claim 1 , wherein the nonionic monomer distinct from the monomer of formula (I) is chosen from the group consisting of acrylamide, methacrylamide, N-isopropylacrylamide, N,N-dimethylacrylamide, N-methylol acrylamide, N-vinylformamide, N-vinylacetamide, N-vinylpyridine, N-vinylpyrrolidone, acryloylmorpholine (ACMO) and diacetone acrylamide.

8. The copolymer according to claim 1 , wherein all of the cationic charges of the copolymer come from quaternary ammonium functional groups.

9. The copolymer according to claim 1 , which consists of, as percentage by mass relative to the total mass of the copolymer:

5 to 45% of at least one cationic monomer whose cationicity comes exclusively from one or more quaternary ammonium functional groups;

50 to 95% of at least one monomer of formula (I); and

5 to 25% of at least one nonionic monomer distinct from the monomer of formula (I).

10. The copolymer according to claim 1 , which consists of, as percentage by mass relative to the total mass of the copolymer:

5 to 45% of at least one cationic monomer whose cationicity comes exclusively from one or more quaternary ammonium functional groups;

55 to 95% of at least one monomer of formula (I); and

at least one nonionic monomer distinct from the monomer of formula (I).

11. The copolymer according to claim 2 , wherein the monomer of formula (I) is chosen from the group consisting of:

poly(ethylene glycol)(meth)acrylate in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =H; n=2 to 200;

methyl-poly(ethylene glycol)(meth)acrylate, also called methoxy-poly(ethylene glycol)(meth)acrylate, in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =CH 3 ; n=2 to 200;

alkyl-poly(ethylene glycol)(meth)acrylates in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =C 1 -C 30 alkyl; n=2 to 200; and

phenyl-poly(ethylene glycol)(meth)acrylates, also called poly(ethylene glycol)phenyl ether(meth)acrylate, in which R 1 =H or CH 3 ; Z=C(═O)—O—; R 2 =phenyl; n=2 to 200.

12. The copolymer according to claim 11 , wherein the monomer of formula (I) is chosen from the group consisting of poly(ethylene glycol)(meth)acrylates and methyl-poly(ethylene glycol)(meth)acrylates, having a molar mass of between 80 and 8000 g/mol.

13. The copolymer according to claim 2 , wherein the cationic monomer is chosen from the group consisting of quaternized dimethylaminoethyl acrylate (ADAME), quaternized dimethylaminoethyl methacrylate (MADAME), dimethyldiallylammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (APTAC) and methacrylamidopropyltrimethylammonium chloride (MAPTAC).

14. The copolymer according to claim 7 , wherein the nonionic monomer distinct from the monomer of formula (I) represents less than 25% by mass of the copolymer.

15. The copolymer according to claim 2 , wherein all of the cationic charges of the copolymer come from quaternary ammonium functional groups.

16. The copolymer according to claim 2 , which consists of, as percentage by mass relative to the total mass of the copolymer:

5 to 45% of at least one cationic monomer whose cationicity comes exclusively from one or more quaternary ammonium functional groups;

50 to 95% of at least one monomer of formula (I); and

5 to 25% of at least one nonionic monomer distinct from the monomer of formula (I).

17. A cosmetic or detergent formulation comprising the copolymer according to claim 1 .