以通用聚苯乙烯(GPPS)为原料,液溴为溴化试剂,无水三氯化铝-铝粉为复合催化体系,采用溶液法合成了溴化聚苯乙烯(BPS).讨论了溴化时间、主链卤代抑制剂(BHSA)、液溴、催化剂等对聚苯乙烯(PS)溴化的影响.结果表明,BPS的溴含量随溴化时间的增加而提高,但也使BPS的摩尔质量显著下降,而主链溴代抑制剂则可改善BPS的断链.增加液溴量和三氯化铝的用量,虽BPS中溴含量增加了,但主链骨架上的溴化使产物颜色加深.提高溴化反应温度,BPS的摩尔质量大为下降.1 H NMR分析表明,增加溴化时间、增加液溴量和主链抑制剂量可有效增加苯环上溴代含量,而增加催化剂用量和升高溴化温度却使苯环上的溴代含量减少.BPS在300℃的热失重低于5％.通过溶液共混制备了GPPS/BPS的共混膜,用原子力显微镜观察了共混物的表面形貌.由结果可知,GPPS和BPS的共混体系相容性差,当共混质量比达1∶1时,BPS仍自成一相分散在连续的PS相中.%General purpose polystyrene ( GPPS) was brominated by liquid bromine with aluminum chloride-aluminum as catalyst in ethylene dichlorine ( EDC) to prepare brominated polystyrene ( BPS). The effect of bromination time, liquid bromine, catalyst and backbone halogenation suppression additive ( BH-SA) on bromination of polystyrene were studied in this work. The results showed that increase of bromination time results in the increase of the bromine content in BPS, but the marked decrease of the molecular weight of BPS. BHSA can suppress the occurrence of backbone-breaking in BPS. To increase the addition of the bromine and aluminum chloride arguments the bromine content in BPS, but made the bromination arise along the GPPS backbone. The enhancement of the bromination temperature caused the decrease of molecular weight of BPS distinctly. ' H NMR analysis elucidated that the increases of bromination time, addition of bromine and BHSA were effective to increase the bromine on the benzene ring, and the increases of the catalyst content and bromination temperature decreased the content of bromine on the benzene ring. The loss weight of BPS at 300 X. Was less than 5 wt%. The blend of GPPS/BPS was prepared in solution, and the film was formed by spinning coating, drying and annealing. Atom force microscope was used to observe the morphology of the blend surface. The results showed that the compatibility of GPPS/BPS was bad, and BPS as a dispersed phase was still encapsulated in continuous GPPS phase even though the blend mass ratio of GPPS/BPS reached at 1:1.
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