Abstract: Process for the selective hydrogenation of double olefinic bonds present in polymers and copolymers of conjugated dienes, which comprises: (a) preparation of a hydrocarbon solution of the (co)polymer to be hydrogenated, optionally containing a modifier (C); (b) addition to the above solution of the (co)polymer to be hydrogenated of a catalytic solution formed “in situ” comprising: (b1) at least one bis-(cyclopentadienyl)titanium derivative having general formula (I) (C5H5)2Ti(R) (R1), wherein R and R1, the same or different, are halogens, preferably R?R1?Cl; the above compound (I) being dispersed in one or more non-solvent diluents; (b2) at least one organo-derivative having general formula (II) M(R2)(R3), wherein M is selected from zinc and magnesium, and R2 and R3, the same or different, are selected from C1-C16 alkyls, preferably C1-C8; (b3) at least one modifier (C); the above selective hydrogenation being carried out in a hydrogen atmosphere until the disappearance of the double olefinic bonds.

Abstract: A process for the preparation of low branch content polybutadiene comprising: (a) a first butadiene polymerisation stage; (b) treatment of the polymer solution obtained upon completion of stage (a) with a coupling agent selected from: (i) polyunsaturated natural oils; (ii) butadiene and/or isoprene oligomers; (iii) butadiene and/or isoprene co-polymers with vinylarene monomers; the unsaturations present in compounds (i)-(iii) being at least partially substituted with groups selected from epoxides, anhydrides and esters; (c) recovery of the low branch content polybutadiene obtained upon completion of stage (b)

Abstract: Process for the preparation of polybutadiene with a low branching degree which comprises: (a) a first polymerization step of butadiene in the presence of organic solvents and in the presence of a catalytic system comprising (a1) a derivative of neodymium; (a2) an aluminum alkyl having general formula (I) AlR1R2R3; (a3) an organo aluminum derivative containing at least one halogen atom, preferably chlorine; the above first step being carried out up to a conversion of butadiene >98% to give a linear polybutadiene (gm=1) with a content of 1,4-cis units greater than 93% and a Mw/Mn ranging from 2.2 to 2.9; (b) treatment of the polymeric solution obtained at the end of step (a) with a peroxide, (c) recovery of the polybutadiene with a low branching degree obtained at the end of step (b).