BRANCHED POLYDIENES AND RUBBER MIXTURES BASED ON THEM Russian patent published in 2023 - IPC C08F2/44 C08F4/52 C08F4/54 C08F36/04 C08F36/06 C08F8/00 C08L9/00 

FIELD: synthetic polymers.

SUBSTANCE: group of inventions relates to the production of synthetic polymers used in the production of tires and rubber technical products for the electrical industry and other areas. A branched polydiene is described, modified by the introduction of at least one plasticizer, which is a low-molecular polymer with a molecular weight of 1,500 to 50,000 g/mol, and characterized by a Mooney viscosity of 40 to 49 Mooney conventional units, where a branched polydiene is characterized by a branching index expressed in the mechanical loss tangent tg δ 1,200% equal to 4.7 to 5.3, measured with variable shear amplitude in the amplitude range from 10 to 1,200%, with a frequency of 0.1 Hz, at a temperature of 100°C. Also described is a method for producing a branched polydiene by polymerization of a conjugated diene, including the preparation of a catalytic complex including a lanthanide compound, an organoaluminium compound, a conjugated diene and a halogen-containing component, polymerization of the conjugated diene in the presence of the specified catalytic system, post-polymerization modification with at least one branching agent, selected from the group consisting of halogen-containing compounds, phosphorus-nitrogen compounds, or mixtures thereof, stopping, introducing at least one plasticizer into the polymer, which is a low-molecular-weight polymer with a molecular weight from 1,500 to 50,000 g/mol, degassing, and polymer drying. A branched polydiene obtained by this method and a rubber mixture based on such polydienes are described. The polydiene obtained according to the invention has improved processability, better distribution of the filler in the polymer matrix, and rubber compounds based on it are characterized by improved elastic-hysteresis properties (namely, Mooney viscosity ML(1+4), Mooney units , Payne effect Δ (G'1% - G'50%), kPa, Tan δ 60°C at 10% strain).

EFFECT: production of a branched polydiene characterized by a Mooney viscosity of 40 to 49 Mooney conventional units and the branching index, characterized by the mechanical loss tangent tg δ (1,200%) from 4.7 to 5.3.

16 cl, 4 tbl, 21 ex