PROCESS FOR THE PREPARATION OF BRANCHED POLYBUTADIENE WITH A HIGH CONTENT OF 1,4-CIS UNITS

摘要

Process for the preparation of polybutadiene effected by the polymerization of butadiene in an aliphatic and/or cyclo-aliphatic solvent in the presence of a catalytic system prepared in situ which comprises: (i) a carboxylate of neodymium soluble in the process solvent containing a variable quantity of water, the H2O/Nd molar ratio ranging from 0.001/1 to 0.50/1; (ii) an alkyl compound of aluminum; (iii) an alkyl compound of aluminum in which at least one bond of Al consists of an Al-Cl bond; The total Al/Nd molar ratio ranging from 4/1 to 12/1, and the Cl/Nd molar ratio ranging from 2/1 to 6/1.