METHOD OF PRODUCING BROMOBUTYL RUBBER Russian patent published in 2013 - IPC C08C19/12 C08C19/14 C08F8/20 C08F8/22 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing bromated butyl rubber and can be used in petrochemical and chemical industry. Bromation of butyl rubber involves treating 10-25% butyl rubber solution in a C₅-C₈ hydrocarbon solvent with bromine water, followed by neutralisation of the reaction mass, adding stabilisers and an anti-agglomerant, water degassing and drying the bromobutyl rubber. Bromine water is prepared by dissolving bromine in water or electrolysis of an aqueous solution containing bromine ions. Excess bromine in the bromobutyl rubber solution is neutralised using an organic acid and/or alkali or alkali-earth metal sulphite. Neutralisation is carried out in a single step by treating the reaction mass with calcium or sodium sulphite or in two steps, the first step including pre-treatment of the reaction mass with an organic acid and the second step including addition of sodium sulphite to the reaction mass.

EFFECT: high resistance of butyl rubber to premature vulcanisation, low cost of degassing rubber and extraction of recycled solvent.

4 cl, 2 tbl, 14 ex