Patent ID: 8507397

Claim:
A method of producing a catalytic system for polymerization based on a rare earth metal salt comprising introducing an organometallic compound of formula (III): in which, M is a metal belonging to the 2 nd column of the Periodic Table; R 1 , R 2 , R 3 and R 4 , which are identical to or different from one another, are hydrogen atoms or linear or branched alkyl substituents, or aryl substituents, which are substituted or unsubstituted, optionally bonded together to form at least one ring composed of 5 or 6 atoms, or at least one aromatic ring; R and R′, which are identical to or different from one another, denote linear or branched alkyl substituents, or aryl substituents, which are substituted or unsubstituted; L is a Lewis base; x is an integer which is equal to 0, 1, 2, 3 or 4; m is an integer having a value ranging from 0 to 3; n is an integer having a value ranging from 1 to 3, as an alkylating co-catalyst in the catalytic system.