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采用邻甲基苯酚钾(o-ROK)为助引发剂,研究了正丁基锂(n-BuLi)/o-ROK/2G/异戊二烯/二甲苯聚合体系的聚合规律。结果表明,加入o-ROK对异戊二烯转化率影响不大;o-ROK/Li(摩尔比,下同)从0增加到0.5时,链转移数(Nt)迅速增大;当o-ROK/Li大于1.0时,Nt变化缓慢;聚合物的1,2-结构和3,4-结构摩尔分数随o-ROK/Li的增大而减少,1,4-结构的摩尔分数则升高。当o-ROK/Li大于0.5时,曲线的变化趋势变缓。这表明体系中活性种PLi·2G络合体的调节结构能力大于PK,PLi以及它们的缔合体等活性种。
The polymerization of n-BuLi / o-ROK / 2G / isoprene / xylene polymerization system was studied by using o-ROK as co-initiator. The results showed that adding o-ROK had little effect on the conversion of isoprene; the number of chain transfer (Nt) increased rapidly when the content of o-ROK / Li increased from 0 to 0.5; When ROK / Li is greater than 1.0, Nt changes slowly. The 1,2-structure and 3,4-structure mole fraction decrease with the increase of o-ROK / Li and the mole fraction of 1,4-structure increases . When o-ROK / Li is greater than 0.5, the trend of the curve slows down. This indicated that the regulatory capacity of the active species PLi · 2G complex in the system is greater than those of active species such as PK, PLi and their associations.