The invention relates to methods for achieving a step increase in the Mooney viscosity in production of high-molecular-weight polybutadiene having >95% by weight content of cis-1,4 units and <1% by weight 1,2-vinyl content, characterized in that 1) at least one monomer selected from butadiene and/or isoprene is polymerized at temperatures of from −20° C. to 150° C. in the presence of at least one inert, organic solvent and in the presence of at least one catalyst based on neodymium carboxylate, 2) the polymerization is then terminated by addition of protic compounds and 3) then sulphur chlorides are added to the polymer, and prior to addition these sulphur chlorides are treated with a carboxylic acid, fatty acid and/or fatty acid ester.

Without significantly impacting monomer conversion, the cis-1,4 mer content of conjugated diene mer in polymers can be increased by adding one or more Lewis bases to a catalyst composition that includes a Group 3 metal atom-containing carboxylate. This effect can be seen even at above average monomer concentrations.

Without significantly impacting monomer conversion, the cis-1,4 mer content of conjugated diene mer in polymers can be increased by adding one or more Lewis bases to a catalyst composition that includes a Group 3 metal atom-containing carboxylate. This effect can be seen even at above average monomer concentrations.

The present disclosure relates to the technical field of preparation of syndiotactic 1,2-polybutadiene (s-PB), in particular to a catalytic system and use thereof, and a preparation method of s-PB. In the present disclosure, the catalytic system includes an iron-containing organic compound, an azodicyano compound, an organoaluminum compound, and a free radical scavenger; where an iron element in the iron-containing organic compound, the azodicyano compound, the organoaluminum compound, and the free radical scavenger have a molar ratio of 1:(0.5-10):(5-100):(1-1000); and the free radical scavenger is selected from the group consisting of a sterically hindered phenol, a sterically hindered amine, and a phosphorus-containing antioxidant. The catalytic system can prepare the s-PB with a high activity at a high temperature, and the s-PB has a melting point of 60° C. to 130° C. with an extremely low gel content or even no gelation.

The present disclosure relates to the technical field of preparation of syndiotactic 1,2-polybutadiene (s-PB), in particular to a catalytic system and use thereof, and a preparation method of s-PB. In the present disclosure, the catalytic system includes an iron-containing organic compound, an azodicyano compound, an organoaluminum compound, and a free radical scavenger; where an iron element in the iron-containing organic compound, the azodicyano compound, the organoaluminum compound, and the free radical scavenger have a molar ratio of 1:(0.5-10):(5-100):(1-1000); and the free radical scavenger is selected from the group consisting of a sterically hindered phenol, a sterically hindered amine, and a phosphorus-containing antioxidant. The catalytic system can prepare the s-PB with a high activity at a high temperature, and the s-PB has a melting point of 60° C. to 130° C. with an extremely low gel content or even no gelation.

A tire component formed from a rubber composition comprises a majority weight percent of renewable materials. The rubber composition comprises, based on 100 parts per weight (phr) of elastomer: a blend of at least two rubber elastomers selected from a group consisting of: from about 15 phr to about 50 phr polybutadiene; up to about 20 phr of styrenebutadiene copolymer; up to about 90 phr of natural rubber; a bio-derived resin material; a vegetable triglyceride oil; and a bio-derived filler comprising silica and carbon black filler. The carbon black filler is at least partially derived from a bio-based feedstock prior to its addition to the rubber composition. The resin and the silica are also derived from renewable materials. In some embodiments, the contemplated polybutadiene may be from mass balanced feedstocks.

A tire component formed from a rubber composition comprises a majority weight percent of renewable materials. The rubber composition comprises, based on 100 parts per weight (phr) of elastomer: a blend of at least two rubber elastomers selected from a group consisting of: from about 15 phr to about 50 phr polybutadiene; up to about 20 phr of styrenebutadiene copolymer; up to about 90 phr of natural rubber; a bio-derived resin material; a vegetable triglyceride oil; and a bio-derived filler comprising silica and carbon black filler. The carbon black filler is at least partially derived from a bio-based feedstock prior to its addition to the rubber composition. The resin and the silica are also derived from renewable materials. In some embodiments, the contemplated polybutadiene may be from mass balanced feedstocks.

The present invention relates to a method for preparing a diene-based rubber polymer having relatively low gel content and high swelling index while having high polymerization conversion rate, a diene-based rubber polymer prepared therefrom and an acrylonitrile-butadiene-styrene graft copolymer with a core-shell structure comprising the same as a core. Accordingly, the method for preparing a diene-based rubber polymer and the acrylonitrile-butadiene-styrene graft copolymer with a core-shell structure comprising the diene-based rubber polymer prepared therefrom can be easily applied to the industries requiring them, in particular, an impact reinforcing agent industry.

The present invention relates to a method for preparing a diene-based rubber polymer having relatively low gel content and high swelling index while having high polymerization conversion rate, a diene-based rubber polymer prepared therefrom and an acrylonitrile-butadiene-styrene graft copolymer with a core-shell structure comprising the same as a core. Accordingly, the method for preparing a diene-based rubber polymer and the acrylonitrile-butadiene-styrene graft copolymer with a core-shell structure comprising the diene-based rubber polymer prepared therefrom can be easily applied to the industries requiring them, in particular, an impact reinforcing agent industry.

The invention relates to a method of manufacturing conjugated diene-based polymers. The conjugated diene-based polymers are obtained by polymerizing conjugated diene monomers or conjugated diene monomers and vinyl aromatic monomers using an initiator, wherein the initiator is obtained by reacting a divinylarene-like compound represented by the formula (1) with an organic alkali metal; A and B are C.sub.nH.sub.2n+1 or an aromatic ring, n is 0~5, A and B can be the same or different, and Q is an aromatic ring; wherein the molar ratio of the divinylarene-like compound to the effective active organic alkali metal is 1.3-5.0. The present invention further relates to a rubber comprising the conjugated diene-based polymers, and a tire comprising the rubber.

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