【摘要】 采用乳聚一步法合成了端澳基液体聚丁二烯,经IR和VPO分析,其平均官能度(?)=2,分子结构为Br(Bd) nCBr2(Bd) mCBr2 (Bd)n Bt(m>n)。当CBr4,乳化剂S和引发剂P用量分别为20％、5％和3.5％—4.5％,聚合温度60—75℃,反应18—24h时,Bd转化率为90％以上。研究表明,CDr4用量对转化率,收率和(?)n有明显的影响,当其用量由15％提高到40％时,(?)n由7800下降到4200。聚合过程生成的调聚物可以回收并可作调节剂用。加有防老剂2246的产物在密封和室温条件下,可贮存1.5a。更多还原

【Abstract】 Dibromopolybutadiene (DBBD) liquid rubber was synthesized from butadiene by emulsion polymerization in the presence of carbon tetrabromide as chain transfer agent.When the usage of CBr4,emulsifier S and initiator P were 20%,5% and 3.5%-4.5%, respectively, polymerization temperature was 60-75℃ and reaction time was within 18-24 h, the polymerization conversion could reach over 90%.The polymer obtained was characterized by infrared absorption spectrometry, VPO and chemical analysis, and the average functionality calculated was approximately 2. The molecule structure of DBBD was represented by the following formula:Br ( Bd ) nCBr2 ( Bd ) mCBr2 ( Bd )n’ Br, where m >> n.It was found that the dosage of CBr4 had an important effect on the conversion of polymerization and the average molecular weight of polymer obtained, and when its usage was increased from 15% to 40%, the number average molecular weight of the polymer obtained decreases from 7800 to 4 200.Thus, it was possible to control the viscosity of DBBD to meet the specific requirements.更多还原