METHOD OF PRODUCING RUBBER MIXTURE FOR MAKING CAR TYRES Russian patent published in 2013 - IPC C08J3/20 C08L21/00 B01F5/08 

FIELD: chemistry.

SUBSTANCE: invention relates to production of a rubber mixture for making car tyres based on unsaturated rubber. The rubber mixture is prepared in a rubber mixer in two steps. The first step involves feeding into the rubber mixer rubber, technical carbon, softening agents, protective wax, N-isopropyl-N'-phenyl-n-phenylenediamine, polymerised 2,2,4-trimethyl-1,2-dihydroquinoline, N-cyclohexyl thiophthalimide, zinc oxide, stearic and oleic acid, after which the ingredients are mixed at 80°C for 4-5 minutes with rotor speed of 60 rpm. The second step involves feeding vulcanisation accelerators and mixing at 60°C for 2-3 minutes at rotor speed of 30 rpm. The obtained rubber mixture is subjected to low-frequency mechanical vibrations. The mixture is then passed through a cascade of series-connected dispersers, after which the treated mixture is vulcanised. Each cascade consists of 2-3 dispersers in form of de Laval nozzles. Pressure drop at each disperser on each cascade is equal to 250000-350000 Pa. The mixture fed through cascades of dispersers by a pump and the pumping pressure is greater than the total pressure drop at cascades by 1.2-1.5 times. Sulphur is fed into the critical part of the nozzle of the fist disperser of the first cascade.

EFFECT: invention increases uniformity of distribution of components, particularly sulphur and carbon, in the rubber mixture.