【摘要】 本文应用氘醇淬灭法测定了钕化合物-烷基铝-丁二烯聚合体系的活性中心浓度.对五种钕化合物和三种烷基铝所组成的不同催化剂体系进行测定的结果表明:其活性中心浓度在0.004～0.08mol/molNd内变化.本文还研究了聚合条件及催化剂组成对活性中心浓度及增长速度常数的影响.结果表明:增长速度常数不随烷基铝及钕化合物的种类而变化,因此,对于不同组成的催化剂,其聚合活性的差别主要在于活性中心浓度的变化.更多还原

【Abstract】 The tritiated alcohol quench method has been used for determining the number of active centers in the polymerization systems of Nd compounds-Al （i-Bu）₂GlAlR₃-butadiene. The number of active centers in this polymerization systems has been shown to lie in the range of 0.004锝?.08 mol/mol Nd for catalytic systems in which five neodymium compounds and two aluminium alkyls reacted with each other. In the present study the influence of polymerization condition and catalyst composition on active centers and propagation rate constants were investigated. The data obtained show that the propagation rate constant does not depend on the nature of A1R₃ and Nd compounds. Thus, it can be concluded that the difference observed in catalyst activities is related to the number of active centers formed.更多还原