Patent ID: 8193287

Claim:
A process comprising reacting a butadiene polymer containing aliphatic carbon-carbon double bonds with a phenyltrialkylammonium tribromide, benzyltrialkylammonium tribromide or tetraalkylammonium tribromide in the presence of at least one solvent for the butadiene polymer, to form a brominated butadiene polymer and a phenyltrialkylammonium monobromide, benzyltrialkylammonium monobromide or tetraalkylammonium monobromide by-product, wherein the solvent for the butadiene polymer is not a solvent for the phenyltrialkylammonium monobromide, benzyltrialkylammonium monobromide or tetraalkylammonium monobromide by-product and further the solvent for the phenyltrialkylammonium monobromide, benzyltrialkylammonium monobromide or tetraalkylammonium monobromide by-product is added to the reaction mixture when from about 25 to 90% of the aliphatic carbon-carbon double bonds in the butadiene polymer have been brominated, and the remainder of the bromination reaction is conducted in the presence of the solvent for the phenyltrialkylammonium monobromide, benzyltrialkylammonium monobromide or tetraalkylammonium monobromide by-product.