低分子量聚苯乙烯悬浮聚合工艺

以过氧化二苯甲酰为引发剂,聚乙烯醇为悬浮分散剂,叔十二烷基硫醇为链转移剂,通过悬浮聚合的方法制得了具有可控分子量的白色颗粒状聚苯乙烯。考察了引发剂、分散剂、链转移剂的添加量、反应温度、反应时间、搅拌速度、水和单体比例等对聚合产物分子量和收率的影响。研究表明本合成最适宜的反应条件为:反应温度75~80℃,反应时间7小时,V水/V单体=8,m引发剂/m单体=10%,m分散剂/m单体=3.5%,m硫醇/m单体=3%时,得到的产物分子量1.2万左右。

Suspension Polymerization Process of Low Molecular Weight Polystyrene

With dibenzoyl peroxide as initiator, polyvinyl alcohol as suspension dispersant, Tert-Dodecyl mercaptan （TDM） as chain transfer agent, white particulate polystyrene with controlled molecular weight was got by the method of suspension polymerization. The amount of initiator, dispersing agent, chain transfer agent, reaction temperature, reaction time, stirring speed, the ratio of water and styrene were considered as reaction affecting factors on the yield and molecular weight. Studies showed that the most suitable reaction conditions as follows： under 75-80 ℃/7 hours, the volume ratio of water, BPO, PVA, TDM and were 8, 10 %, 3.5 %, and 3 % respectively, the molecular weight polystyrene obtained was about 12,000.