Patent ID: 7674862
Filing Date: 2010-03-09
Classification: C08C,C08F

Abstract:
1. A process comprising a) brominating a butadiene polymer to form a crude reaction mixture containing a brominated butadiene polymer dissolved or dispersed in a solvent; b) distilling a portion of the solvent from the crude reaction mixture to form (1) a distillate containing a portion of the solvent and (2) a concentrated solution or slurry of the brominated butadiene polymer in another portion of the solvent, such that from about 20 to 70% of the solvent is removed from the crude reaction mixture to produce a concentrated solution or slurry that contains from 65 to 80 percent by weight of the solvent, and then c) recovering the brominated butadiene polymer from the concentrated solution or slurry by (1) precipitating the brominated butadiene polymer from the concentrated solution or slurry by contact with an antisolvent, (2) thermally stripping the remaining solvent from the concentrated solution or slurry by forming the concentrated solution or slurry into droplets and heating the droplets to a temperature sufficient to drive off most or all of the remaining solvent, (3) a combination of both (1) and (2), or (4) a combination of (1), (2) or (3) with a washing step.