摘要 |
Preparing brominated styrenic polymer by maintaining a mixture formed from (i) brominating agent, (ii) a solvent solution of styrenic polymer, and (iii) aluminum halide catalyst, at -20 to +20 ~ C, and terminating bromination in 20 minutes or less. New brominated anionic styrenic polymers have better melt flow and/or lower initial .DELTA.E values than the best previously-known brominated anionic styrenic polymers. Other features of such new polymers include high thermal stabilities at 320~ C and/or very low initial color values. Brominated styrenic polymers, especially brominated anionic styrenic polymers, are useful as flame retardants for thermoplastic polymers. |