摘要 |
A process for halogenating a copolymer of a C4-C7 isomonoolefin, eg. isobutylene, and a para-alkylsyrene, e.g., para-methylstyrne, is disclosed. Increased halogenation efficiency is achieved by conducting the reaction under free radical halogenation conditions and in the presence of an oxidizing agent, e.g. hydrogen peroxide, which oxidizes hydrogen halide generated in-situ in the reaction back to free halogen. The oxidizing agent is preferably not added to the reaction medium until after first stage halogenation is substantially completed.
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