| abstract |
A brominated polystyrene product made by the process comprising pretreating a solution of a polystyrene reactant comprising from about five to about 20 percent by weight of the polystyrene reactant, in a halogenated hydrocarbon solvent with at least about 0.1 percent by weight of an additive to suppress halogenation of the polystyrene backbone, prior to brominating the polystyrene in the presence of a catalyst; subsequently adding a metal halide bromination catalyst to the solution, capable of effecting bromination of the ring without causing crosslinking of the polystyrene; adding to the solution from about 1 to about 3.4 moles of a brominating agent, per mole of polystyrene repeating units; reacting the polystyrene with the brominating agent at a temperature of from about −20° C. to about 50° C., and isolating the brominated polystyrene. A brominated polystyrene is provided having a backbone halogen content of less than about 750 ppm and a ΔE color of from about 5 go about 19. |