Method for preparing brominated copolymer of conjugated diene and styrene monomer

A brominated copolymer of at least one conjugated diene and at least one styrene monomer is prepared such that at least 45% but not more than 70% of the non-aromatic double bonds in the copolymer are brominated. The prepared brominated copolymer can be used as a flame retardant and shows an unexpected small domain size after dissolution in a subsequently polymerized styrene monomer. 制备至少一种共轭二烯和至少一种苯乙烯单体的溴化共聚物使得所述共聚物中至少45％但不超过70％的非芳族双键被溴化。所制得的溴化共聚物可用作阻燃剂，并且在随后聚合的苯乙烯单体中溶解后表现出出人意料的小畴尺寸。