Abstract:
A process for the preparation of branched polybutadiene having a high content of 1,4-cis units which comprises polymerizing butadiene in the presence of at least one organic solvent, and in the presence of: a) a catalytic system prepared in situ including: (a1) at least one neodymium carboxylate, (a2) at least one alkyl compound of aluminum, (A3) at least one alkyl compound of aluminum containing at least one halogen atom, and b) at least one organic ester containing at least one halogen atom. Said branched polybutadiene having a high content of 1,4-cis units, depending on the branching degree and molecular weight distribution, can be advantageously used in various applications ranging from the modification of plastic materials [production, for example, of high impact polystyrene (HIPS)] to the production of tires, in particular the production of treads and/or of sidewalls of tires.
Abstract:
A process for the preparation of an elastomeric polymer of ethylene which comprises polymerizing, in suspension, a mixture of monomers comprising ethylene, at least one a-olefin having from 3 to 12 carbon atoms, possibly at least one non-conjugated diene having from 4 to 20 carbon atoms, in the presence of a catalytic system comprising:—a suspension in oil of at least one catalyst selected from compounds containing vanadium;—-at least one co-catalyst, as such, selected from compounds containing aluminium; at least one activator, as such, selected from compounds containing chlorine.
Abstract:
A process for the preparation of an elastomeric polymer of ethylene which comprises polymerizing, in suspension, a mixture of monomers comprising ethylene, at least one a-olefin having from 3 to 12 carbon atoms, possibly at least one non-conjugated diene having from 4 to 20 carbon atoms, in the presence of a catalytic system comprising: —a suspension in oil of at least one catalyst selected from compounds containing vanadium; —at least one co-catalyst, as such, selected from compounds containing aluminum; at least one activator, as such, selected from compounds containing chlorine.
Abstract:
Process for the preparation of a diene polymer or a random vinyl arene-diene copolymer comprising anionically (co)polymerizing at least one conjugated diene monomer, optionally in the presence of at least one vinyl arene, in the presence of at least one hydrocarbon solvent, at least one lithium-based initiator and at least one organic compound containing at least one nitrox- ide group having general formula (I) or (II): wherein: R1, R2, R3 and R4, mutually identical or different, represent a hydrogen atom; or are selected from C1-C20, preferably C1-C8, linear or branched alkyl groups optionally containing heteroatoms such as, for example, oxygen, nitrogen, sulphur, optionally substituted cycloalkyl groups, optionally substituted C1-C20, preferably C1-C8, linear or branched alkoxy groups, optionally substituted aryl groups; -x is an integer ranging from 0 to 7, preferably ranging from 4 to 5; -y is an integer ranging from 1 to 3, preferably ranging from 1 to 2.
Abstract:
A process for the preparation of branched polybutadiene having a high content of 1,4-cis units which comprises polymerizing butadiene in the presence of at least one organic solvent, and in the presence of: a) a catalytic system prepared in situ including: (a1) at least one neodymium carboxylate, (a2) at least one alkyl compound of aluminum, (A3) at least one alkyl compound of aluminum containing at least one halogen atom, and b) at least one organic ester containing at least one halogen atom. Said branched polybutadiene having a high content of 1,4-cis units, depending on the branching degree and molecular weight distribution, can be advantageously used in various applications ranging from the modification of plastic materials [production, for example, of high impact polystyrene (HIPS)] to the production of tyres, in particular the production of treads and/or of sidewalls of tyres.