| abstract |
The present invention relates to a process for preparing a diene elastomer, such as a butadiene homopolymer or copolymer. The invention is particularly applicable to obtaining a polybutadiene with a high rate of cis-1,4 linkages having both a Mooney viscosity equal to or greater than 40 and a polydispersity index of less than 2.1.n n n The process according to the invention comprises a reaction of a catalytic system with at least one conjugated diene monomer to be polymerized and the catalytic system is based on at least: optionally a conjugated diene of preformation, a salt of one or more rare earth metals, such as a salt of a carboxylic acid or of an organic phosphoric acid, an inert hydrocarbon solvent, an alkylating agent comprising an allyl derivative of aluminum of formula R " n A1R ' 3-n , where R' is a saturated or unsaturated alkyl group or a hydride, where R" is an allyl group and where n is an integer between 1 and 3, and a halogen donor which belongs to the family of alkylaluminium halides, excluding alkylaluminium sesquihalides. |