Process for the preparation of linear or branched 1,4-cis polybutadiene

摘要

A process is described for the preparation of 1,4-cis polybutadiene by means of the polymerization of 1,3-butadiene, carried out in one or more solvents and in the presence of a catalytic system which comprises one or more catalysts selected from cobalt complexes, preformed or formed in situ, having general formula (I) Co<(z)>LbWm wherein (z), the cobalt oxidation number, is 2 or 3; b = 1, 2, 3; m = 0, 1, 2; W is selected from Br, Cl, acetylacetonate, carboxylate, characterized in that: L is a ligand having general formula (Ia) <CHEM>