A method for producing branched modified rubber and a rubber composition comprising branched modified rubber prepared by the method, and use thereof

[0096] Example 1. (Comparison, according to prototype) Polymerization in the presence of n-butyllithium and pyrrolidine

[0097] Production of styrene-butadiene rubber in a 2L Buchi reactor with metal cups equipped with stirrer, jacket for temperature control, fittings and specific removable metal for feeding reagents feeder.

[0098] White spirit (984g), butadiene (92.62g), styrene (30.98g), DTHFP (4.0ml) in white spirit (0.32M solution) and 5.95ml white spirit were mixed under the stirrer rotation rate of 50rpm A solution of pyrrolidine (0.2M) was fed to the reactor cooled to -20°C (± 2°C) in nitrogen flow. The stirrer rotation rate was set to 300 rpm, the temperature of the reaction mass was raised to 55° C. at a rate of 7°/min, and when the temperature reached 15° C., 2.88 ml of n-butyllithium in white spirit ( 0.32M solution). After reaching the desired monomer conversion (100%), the polymer was transferred to a cup and filled with the antioxidant Novantox (0.4% by weight per 100 g polymer). Furthermore, the rubber was subjected to aqueous degassing in an oil bath at 150°C. The resulting hydrous rubber was dried on rolls at a temperature of 85°C.

[0099] The properties of the rubber are given in Table 1. The characteristics of the tread rubber obtained from this rubber are shown in Table 2.

[0100] Example 2. (Comparison, according to prototype) Polymerization in the presence of n-butyllithium and oligosiloxane Coatosil MP-200

[0101] Oligomeric siloxane Coatosil MP-200 has the following structure:

[0102]

[0103] Production of styrene-butadiene rubber in a 2L Buchi reactor with metal cups equipped with stirrer, jacket for temperature control, fittings and specific removable metal for feeding reagents feeder.

[0104] Petroleum solvent (987 g), butadiene (100.6 g), styrene (33.38 g) and DTHFP (2.9 ml) in petroleum solvent (0.32 M solution) were fed into the nitrogen stream at a stirrer rotation rate of 50 rpm Cool the reactor to -20°C (±2°C). The stirrer rotation rate was set to 300 rpm, the temperature of the reaction mass was raised to 55° C. at a rate of 7°/min, and when the temperature reached 15° C., 2.5 ml of n-butyllithium in petroleum solvent ( 0.305M solution). After reaching the desired monomer conversion (100%), the reaction mixture was heated to 80 °C and 1.9 ml of a branching and modification reagent (Coatosil MP-200) in toluene (0.1 M solution) was added , and the branching and modification process was carried out for 30 minutes. The polymer was then transferred to a cup and filled with the antioxidant Novantox (0.4% by weight per 100 g of polymer). Furthermore, the rubber was subjected to aqueous degassing in an oil bath at 150°C. The resulting hydrous rubber was dried on rolls at a temperature of 85°C.

[0105] The properties of the rubber are given in Table 1. The characteristics of the tread rubber obtained from this rubber are shown in Table 2.

[0106] Example 3 (comparative, according to prototype) Polymerization in the presence of n-butyllithium and oligosiloxane Silres HP1250

[0107] Oligomeric siloxane Silres HP1250 has the following structure

[0108]

[0109] Styrene-butadiene rubber was prepared according to the procedure described in Example 1, except that the oligosiloxane used was a product under the trade name Silres HP1250, which was added in an amount of 0.3% by weight to the obtained rubber, which uses a 5% toluene solution.

[0110] The properties of the rubber are given in Table 1. The characteristics of the tread rubber obtained from this rubber are shown in Table 2.