Block copolymers that can be used as plasticisers

A method for preparing a block copolymer comprising:

• at least one block A not comprising any phosphonate group, and comprising at least one poly (alkylene oxide) group, and
• at least one block B obtained by polymerization of a monomer B1 or of a mixture of monomers with ethylenic unsaturation comprising at least one monomer B1, wherein a monomer B1 is a monomer with ethylenic unsaturation comprising at least one phosphonate function comprising the steps of:
• b) providing a compound of the following formula (V):
• wherein:
• block A is a block A not comprising any phosphonate group, and comprising at least one poly (alkylene oxide) group,
• L is absent or is a binding group connecting covalently the block A and the group —S—(CS)R10,
• R10 represents an alkyl, an arylalkyl, an aryl, an alkylaryl or a group OR11, NR12R13 or SR14,
• R11, R12, R13 and R14 represent independently an alkyl or an alkenyl, an arylalkyl, an aryl, an alkylaryl, wherein R12 and R13 may be connected together in order to form a ring with the nitrogen atom bearing them,
• c) controlled radical polymerization, or several successive controlled radical polymerizations, comprising the putting into contact:
• of the compound of formula (V),
• of a monomer B1 or a mixture of monomers with ethylenic unsaturation comprising at least one monomer B1, wherein a monomer B1 is a monomer with ethylenic unsaturation comprising at least one phosphonate function, and
• of a source of free radicals.

A method for preparing a block copolymer comprising:

• at least one block A not comprising any phosphonate group, and comprising at least one poly (alkylene oxide) group, and
• at least one block B obtained by polymerization of a monomer B1 or of a mixture of monomers with ethylenic unsaturation comprising at least one monomer B1, wherein a monomer B1 is a monomer with ethylenic unsaturation comprising at least one phosphonate function, comprising the steps of:
• b′) providing a compound of the following formula (V′):
• wherein:
• block B is a block obtained by polymerization of a monomer B1 or of a mixture of monomers with ethylenic unsaturation comprising at least one monomer B1, wherein a monomer B1 is a monomer with ethylenic unsaturation comprising at least one phosphonate function,
• L′ is absent or is a binding group connecting covalently block B and the group —S—(CS)R′10,
• R′10 represents an alkyl, an arylalkyl, an aryl, an alkylaryl, a group OR′11, NR′12R′13 or SR′14,
• R′11, R′12, R′13 and R′14 represent independently an alkyl or an alkenyl, an arylalkyl, an aryl, an alkylaryl, wherein R′12 and R′13 may be bound together in order to form a ring with the nitrogen atom bearing them,
• c′) a controlled radical polymerization, or several successive controlled radical polymerizations, comprising the putting into contact:
• of the compound of formula (V′),
• of a monomer A1 or of a mixture of monomers with ethylenic unsaturation comprising at least one monomer A1, wherein a monomer A1 is a monomer with ethylenic unsaturation comprising at least one poly (alkylene oxide) group, and
• of a source of free radicals.