摘要
用紫外可见光谱法考察了MoO_2Br_2-Al(i-Bu)_2OPhCH_3(-m)催化体系中添加第三组分-烯丙基卤(A11yl-X),对丁二烯聚合的影响.结果表明,MoO_2Br_2的乙酸乙酯溶液在340nm和780nm处有两个特征吸收峰.其中780nm处归属为Mo(V)的自旋允许d-d跃迁吸收峰.烯丙基卤能与Mo形成π络合物,随Al/Mo增加,其电荷迁移峰由340nm移向380nm,且烯丙基卤和丁二烯可分别与Mo(Ⅲ)形成的π络合物,其特征吸收峰均在380nm处.同时表明,Al(i-Bu)_2OPhCH_3(-m)易与烯丙基溴反应,可使烯丙基溴-Mo(Ⅲ)络合物解络合.
The effect of adding the third component to MoO_2Br_2-Al(i-Bu)_2 OPhCH_3 catalyst system on the polymerization of butadiene was studied. Theoe were two charactersitic absorption bands respectively at 340 and 780 nm for the ethyl acetate solution with MoO_2Br_2, and the band at 780nm resulted from the spin-allowed d-d transition of Mo(V). The allyl halogen could form π-complex with molybdenum. As the molar ratio of Al/Mo increased, the peak of the characteristic adsorption band of the electric charge transition was shifted from 340nm to 380nm, and for the π-complex of Mo (Ⅲ) it was at 380nm. Al(i-Bu)_2OPhCH_3 was liable to react with Allyl-Br, which would lead to decomplexation of Mo (Ⅲ)-Allyl-Br complex.
出处
《青岛化工学院学报（自然科学版）》
1992年第4期31-37,共7页
Journal of Qingdao Institute of Chemical Technology(Natural Science Edition)
基金
国家自然科学基金
关键词
聚丁二烯
催化
紫外
光谱学
橡胶
MoO_2Br_2
UV-VIS spectrum
allyl halogen
polybutadiene
