摘要
在聚丙烯基聚偕氨肟(PPAO)—硫脲(TU)体系引发丙烯腈(AN)聚合过程中,将 c(TU)/c(PPAO)摩尔比调节在0.5以上,可以观察到 PPAO、硫脲和硝酸浓度的变化对聚合速度都不产生实质性的影响,但聚合诱导期则随 c(TU)/c(PPAO)摩尔比增大而延长。根据实验结果,得表观聚合速度R_p=2.07e^(-32.6KJ/RT)c^(2.0)(AN)碰撞频率因子极低和引发体系的零级反应是链自由基向初级自由基碰撞终止的特征。
The polymerization of acrylonitrile (AN) initiated by polypropylene—based polyamidoxime (PPAO)—thiourea(TU) system was investigated at c(TU)/c(PPAO)>0.5 molar ratio.It shows that the variation of the concentrations of PPAO,thiourea and nitric acid does not exert an observable influence on the speed of reactions.The overall rate of polymerization (R_p) is R_p=2.07e^(-32.6kJ/RT) c^(2.0)(AN) The zero ordr dependence on PPAO and thiourea concentrations and the lowest value of the collision frequence factor were considered to be a feature of the primary radical termination.
出处
《广州化学》
CAS
1992年第4期9-16,共8页
Guangzhou Chemistry
基金
国家自然科学基金资助
