Polymers functionalized with amino acids or amino acid derivatives, method for synthesizing same, and use thereof as surfactants in cosmetic compositions, particularly nail varnishes

A method for dispersing solid particles in a liquid medium comprising the step of combining said particles with a chain end functionalised polymer of the formula:

• ##STR19## in which:
• the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one ethylenically unsaturated monomer and whose number average molar mass is between 500 and 250,000;
• R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2 H, NH.sub.2, OH or a phenyl group, itself being optionally substituted;
• A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, an amide bond or a peptide chain having 2 to 4 amino acids;
• the COOH and/or NH.sub.2 groups being free or salified.

A method for incorporating solid particles in a composition selected from the group consisting of paint, food, phytosanitary compositions and cosmetic compositions comprising the steps of combining said solid particles with a chain end functionalised polymer of the formula:

• ##STR20## in which:
• the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one ethylenically unsaturated monomer and whose number average molar mass is between 500 and 250,000;
• R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2 H, NH.sub.2, OH or a phenyl group, itself being optionally substituted;
• A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, an amide bond or a peptide chain having 2 to 4 amino acids;
• the COOH and/or NH.sub.2 groups being free or salified;
• and
• adding said combined solid particles and functionalised polymer to said composition.

A surfactant having a formula:

• ##STR21## in which:
• the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one ethylenically unsaturated monomer;
• R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2 H, NH.sub.2, OH or a phenyl group, itself being optionally substituted;
• A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, an amide bond or a peptide chain having 2 to 4 amino acids;
• the COOH and/or NH.sub.2 groups being free or salified.

A method to improve the wetting effect of a liquid medium towards a solid surface or particle comprising the step of adding to said liquid medium an effective amount of a chain end functionalised polymer of the formula:

• ##STR22## in which:
• the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one monomer;
• R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2 H, NH.sub.2, OH or a phenyl group, itself being optionally substituted;
• A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, an amide bond or a peptide chain having 2 to 4 amino acids;
• the COOH and/or NH.sub.2 groups being free or salified.

A method for forming an emulsion comprising the step of combining two liquids with a surfactant to form a liquid--liquid emulsion, said surfactant being a functionalized polymer of the formula:

• ##STR23## in which:
• the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one ethylenically unsaturated monomer,
• R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2 H, NH.sub.2, OH or a phenyl group, itself being optionally substituted,
• A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, an amide bond or a peptide chain having 2 to 4 amino acids,
• the COOH and/or NH.sub.2 groups being free or salified.

A method for incorporating solid particles in cosmetic compositions comprising the steps of combining said solid particles with a functionalized polymer of formula:

• ##STR24## in which:
• the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one ethylenically unsaturated monomer,
• R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2 H, NH.sub.2, OH or a phenyl group, itself being optionally substituted,
• A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, an amide bond or a peptide chain having 2 to 4 amino acids,
• the COOH and/or NH.sub.2 groups being free or salified;
• and adding said combined solid particles and functionalized polymer to said composition.