PROCESS FOR PREPARING BIMODAL OR MULTIMODAL POLYMERS OF CONJUGATED DIENES

摘要

A process of preparing a bimodal or multimodal homopolymer of a conjugated diene or a bimodal or multimodal copolymer of a conjugated diene with another conjugated diene or with a vinyl aromatic compound consists in polymer izing the monomer(s) in a reaction medium at a temperature of between 20.degree.C. and 200.degree.C. in the presence of a catalytic system comprising an organolithium initiator, a barium, strontium or calcium compound, and an organometallic compound of a metal of group 2B or 3A of the periodic classification of elements of the Mendeleev Table and adding hydrogen as a modifying agent to the reaction medium during the course of the polymerization reaction.