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本文报道由(NdCl_3+FeCl_3)·nphen-HAl(i-Bu)_2催化体系引发异戊二烯聚合的结果。在适当Nd/Pe比下,该体系对异戊二烯聚合的活性可超过单一钕或铁催化剂的活性,同时随催化剂中钕和铁含量的不同,所得产物的微观结构变化很大,当体系中钕含量由100％→0时,产物的顺-1,4结构含量由94.4％→22.1％,而3,4结构含量由5.6％→77.9％。Al/M(N=Nd+Fe)比、单体浓度和聚合温度不仅对聚合活性有影响,对产物的微观结构影响也较大。事实表明,该聚合体系中存在着两种过渡金属(Nd和Fe)活性中心,它们按各自的机理进行异戊二烯的聚合。
This paper reports the results of isoprene polymerization initiated by (NdCl_3 + FeCl_3) · nphen-HAl (i-Bu) _2 catalyst system. At the appropriate Nd / Pe ratio, the activity of isoprene polymerization can be more than that of a single neodymium or iron catalyst, and the microstructure of the obtained product varies greatly with the content of neodymium and iron in the catalyst. When the system When the content of neodymium is from 100% → 0, the content of cis-1,4 is from 94.4% → 22.1%, while the content of 3,4 is from 5.6% to 77.9%. Al / M (N = Nd + Fe) ratio, monomer concentration and polymerization temperature affect not only the polymerization activity, but also the microstructure of the product. The facts show that there are two kinds of transition metal (Nd and Fe) active centers in the polymerization system, and they polymerize isoprene according to their respective mechanisms.