METHOD FOR PREPARING CHLOROBUTYL RUBBER Russian patent published in 2004 - IPC

FIELD: rubber industry.

SUBSTANCE: invention relates to chemical modification of rubbers, namely to preparing chlorobutyl rubber. Method is carried out by treatment of butyl rubber solution with tert.-butyl hypochlorite in the amount up to 8 wt.-% per polymer in organic solvent followed by neutralization with alkali and/or sulfite, washing out with water, isolation of the end product by aqueous degassing and drying. For preparing rubber solution method involves using wet butyl rubber crumbs comprising up to 33 wt.-% of water. Mixture of non-polar hydrocarbon solvent and tert.-butyl alcohol taken in the mass ratio in mixture from 24:1 to 3:1 is used as an organic solvent. Method provides avoiding reducing Mooney viscosity values, elevating dosing a chlorinating agent for prevention of reducing chlorine content in rubber. The end product is characterized with good properties of rubber mixtures and physical-mechanical indices of vulcanizate. Method provides simplification and reducing cost in technology manufacturing.

EFFECT: improved preparing method.

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