Process for the preparation of syndiotactic 1,2-polybutadiene in the presence of a catalytic system comprising a pyridyl iron complex

Abstract

Process for the preparation of syndiotactic 1,2-polybutadiene comprising polymerising 1,3-butadiene in the presence of a catalytic system comprising: —at least one pyridyl iron complex having the general formula (I), in which: —Rrepresents a hydrogen atom; or a methyl group; —Rrepresents a hydrogen atom; or is selected from linear or branched C-Calkyl groups; —X, identical or different to one another, represent a halogen atom; or are selected from linear or branched, C-Calkyl groups, —OCORgroups or —ORgroups in which Ris selected from linear or branched C-Calkyl groups; —n is 2 or 3; —at least one aluminoxane having the general formula (II), (R)-AI-O-[-AI(R)—O-]-AI-(R)(ll) in which R, Rand R, identical or different to one another, represent a hydrogen atom, or a halogen atom; or are selected from linear or branched C-Calkyl groups, cycloalkyi groups, aryl groups, said groups being optionally substituted with one or more silicon atoms or germanium; and m is an integer ranging from 0 to 1000; in which the molar ratio between the aluminium present in the aluminoxane having the general formula (II) and the iron present in the pyridyl iron complex having the general formula (I) is ranging from 5 to 20.