Catalytic systems made of a complex of rare earths for stereospecific polymerisation of conjugated dienes

A catalytic polymerization system comprising:

• (i) a rare-earth complex of Formula (II) Ln(A)3(B)n, in which
• Ln is a rare-earth metal from the family of lanthanides or yttrium or scandium,
• A is a ligand chosen from the family of amides,
• B is a Lewis base selected from the group consisting of ethers, amines, phosphates, and thioethers, and
• n is a number ranging from 0 to 3;
• (ii) an alkylating agent;
• (iii) a compound based on an aromatic ring and having at least two heteroatoms chosen from the elements O, N, S, P, and corresponding to the Formula (III):
• wherein
• the R groups are identical to or different from one another, and each represent either:
• a hydrogen atom,
• an aliphatic, cycloaliphatic or aromatic alkyl radical, optionally comprising one or several heteroatoms (N, O, P, S, Si) or one or more halogen atoms,
• a halogen atom,
• a group based on one or more heteroatoms (N, O, P, S, Si);
• x and y are integers from 0 to 6;
• D is a group having a chemical function, one of the atoms of which has a non-bonding pair;
• L being an atom from column 1 of the Periodic Table.

A catalytic polymerization system comprising:

• (i) a rare-earth complex of Formula (II) Ln(A)3(B)n, in which
• Ln is a rare-earth metal from the family of lanthanides or yttrium or scandium,
• A is a ligand chosen from the family of organophosphates, the family of alcoholates, the family of amides, the family of alkyls, aryls or benzyls or the family of borohydrides,
• B is a Lewis base selected from the group consisting of ethers, amines, phosphates, and thioethers, and
• n is a number ranging from 1 to 3;
• (ii) an alkylating agent;
• (iii) a compound based on an aromatic ring and having at least two heteroatoms chosen from the elements O, N, S, P, and corresponding to the Formula (III):
• wherein
• the R groups are identical to or different from one another, and each represent either:
• a hydrogen atom,
• an aliphatic, cycloaliphatic or aromatic alkyl radical, optionally comprising one or several heteroatoms (N, O, P, S, Si) or one or more halogen atoms,
• a halogen atom,
• a group based on one or more heteroatoms (N, O, P, S, Si);
• x and y are integers from 0 to 6;
• D is a group having a chemical function, one of the atoms of which has a non-bonding pair;
• L being an atom from column 1 of the and Periodic Table further comprising a halogen donor compound.

A catalytic polymerization system comprising:

• a rare-earth complex of Formula (II) Ln(A)3(B)n, in which
• Ln is a rare-earth metal from the family of lanthanides or yttrium or scandium,
• A is a ligand chosen from the family of organophosphates, the family of amides, the family of alkyls, aryls or benzyls or the family of borohydrides,
• B is a Lewis base selected from the group consisting of ethers, amines, phosphates, and thioethers, and
• n is a number ranging from 0 to 3;
• (ii) an alkylating agent;
• (iii) a compound based on an aromatic ring and having at least two heteroatoms chosen from the elements O, N, S, P, and corresponding to the Formula (III):
• wherein
• the R groups are identical to or different from one another, and each represent either:
• a hydrogen atom,
• an aliphatic, cycloaliphatic or aromatic alkyl radical, optionally comprising one or several heteroatoms (N, O, P, S, Si) or one or more halogen atoms,
• a halogen atom,
• a group based on one or more heteroatoms (N, O, P, S, Si);
• x and y are integers from 0 to 6;
• D is a group having a chemical function, one of the atoms of which has a non-bonding pair;
• L being an atom from column 1 of the Periodic Table.