Novel block polymers, compositions comprising them, and treatment methods

A cosmetic or pharmaceutical composition comprising, in a physiologically acceptable medium, at least one block copolymer comprising at least one first block and at least one second block, wherein:

• the at least one first block comprises from 0.5 to 35% by weight, relative to the weight of said first block, of at least one silicone monomer chosen from, alone or as a mixture, the following monomers:
• (i) ethylenic monomers of which the ester group comprises silanes and/or siloxanes, of formula:
• wherein:
• R1 is chosen from a hydrogen atom and a methyl group;
• R2, R3, and R4, which are identical or different, are chosen from C1-C6 alkyl groups and —OSi(R5)3 groups wherein R5 is chosen from methyl and ethyl groups;
• n is an integer from 1 to 10;
• (ii) polydimethylsiloxanes macromonomers, or polydimethylsiloxanes having a monoacryloyloxy or monomethacryloyloxy terminal group, of the following formula:
• wherein:
• R8 is chosen from a hydrogen atom and a methyl group;
• R9 is chosen from linear and branched divalent hydrocarbon-based groups having from 1 to 10 carbon atoms and optionally comprising one or two ether —O— bonds;
• R10 is chosen from linear and branched alkyl groups having from 1 to 10 carbon atoms;
• n is an integer ranging from 1 to 300;
• (iii) ethylenic monomers of which the ester group comprises carboxysilane dendrimers of formula:
• wherein:
• R1 is chosen from a hydrogen atom and a methyl group;
• n is an integer from 1 to 10;
• R′2, R″2, R′3 and R″3, which are identical or different, are chosen from C1 to C10 alkyl groups;
• R3 is chosen from C2 to C10 alkylene divalent groups;
• i is an integer from 1 to 10;
• provided that
• when i is an integer from 2 to 10, X(i), which are identical or different, is chosen from —R4—Si—[O—(R′3)(R″3)—X(i-1)]3 groups wherein R4, which are identical or different, is chosen from C2 to C10 alkylene divalent groups;
• and
• when i is 1, X(i) is chosen from a hydrogen atom and C1-C10 alkyl groups;
• (iv) ethylenic monomers of polyhedral oligomeric silsesquioxanes (POSS) or polyhedral oligomeric silicates (POS) type of structure:
• wherein R, being identical or different, is chosen from linear C1 to C10 alkyl groups and cyclic C3 to C12 alkyl groups;
• and
• the at least second one block, being identical to or different from said first block, comprises from 0.5 to 100% by weight, relative to the weight of said second block, of at least one monomer chosen from, alone or as a mixture, monomers of formula (I):
• CH2═C(R1)—COOR2, wherein R1 is chosen from a hydrogen atom and a methyl group, and R2 is chosen from C4 to C12 cycloalkyl groups.

A cosmetic treatment method comprising applying to the skin of the body or face, the lips, nails, eyelashes, eyebrows and/or hair a cosmetic composition comprising, in a physiologically acceptable medium, at least one block copolymer comprising at least one first block and at least one second block, wherein:

• the at least one first block comprises from 0.5 to 35% by weight, relative to the weight of said first block, of at least one silicone monomer chosen from, alone or as a mixture, the following monomers:
• (i) ethylenic monomers of which the ester group comprises silanes and/or siloxanes, of formula:
• wherein:
• R1 is chosen from a hydrogen atom and a methyl group;
• R2, R3, and R4, which are identical or different, are chosen from C1-C6 alkyl groups and —OSi(R5)3 groups wherein R5 is chosen from methyl and ethyl groups;
• n is an integer from 1 to 10;
• (ii) polydimethylsiloxanes macromonomers, or polydimethylsiloxanes having a monoacryloyloxy or monomethacryloyloxy terminal group, of the following formula:
• wherein:
• R8 is chosen from a hydrogen atom and a methyl group;
• R9 is chosen from linear and branched divalent hydrocarbon-based groups having from 1 to 10 carbon atoms and optionally comprising one or two ether —O— bonds;
• R10 is chosen from linear and branched alkyl groups having from 1 to 10 carbon atoms;
• n is an integer ranging from 1 to 300;
• (iii) ethylenic monomers of which the ester group comprises carboxysilane dendrimers of formula:
• wherein:
• R1 is chosen from a hydrogen atom and a methyl group;
• n is an integer from 1 to 10;
• R′2, R″2, R′3 and R″3, which are identical or different, are chosen from C1 to C10 alkyl groups;
• R3 is chosen from C2 to C10 alkylene divalent groups;
• i is an integer from 1 to 10;
• provided that when i is an integer from 2 to 10, X(i), which are identical or different, is chosen from —R4—Si—[O—(R′3)(R″3)—X(i-1)]3 groups wherein R4, which are identical or different, is chosen from C2 to C10 alkylene divalent groups;
• and
• when i is 1, X(i) is chosen from a hydrogen atom and C1-C10 alkyl groups;
• (iv) ethylenic monomers of polyhedral oligomeric silsesquioxanes (POSS) or polyhedral oligomeric silicates (POS) type of structure:
• wherein R, which is identical or different, is chosen from linear C1 to C10 alkyl groups and cyclic C3 to C12 alkyl groups;
• and
• the at least one second block, being identical to or different from said first block, comprises from 0.5 to 100% by weight, relative to the weight of said second block, of at least one monomer chosen from, alone or as a mixture, monomers of formula (I):
• CH2═C(R1)—COOR2, wherein R1 is chosen from a hydrogen atom and a methyl group, and R2 is chosen from C4 to C12 cycloalkyl groups.