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探讨了一系列不同结构和极性的化合物对以稀土催化的丁二烯聚合的影响。这些添加剂中绝大多数降低了催化活性,并使聚合物的分子量上升,而只有烯丙基衍生物虽然降低了催化活性,却使聚合物的分子量下降。从稀土催化剂的活性中心寿命很长和其对普遍用于Ziegler-Natta催化体系的调聚剂的不敏感性看来,稀土催化体系具有一定的特点,其聚合机理有可能与一般过渡金属催化体系不尽相同。
The effects of a series of compounds of different structures and polarities on the polymerization of butadiene catalyzed by rare earths were investigated. The vast majority of these additives reduce the catalytic activity and increase the molecular weight of the polymer, whereas only the allyl derivative reduces the catalytic activity but decreases the molecular weight of the polymer. Rare earth catalyst system has certain characteristics from the viewpoint of long service life of the rare earth catalyst and its insensitivity to the telogen commonly used in the Ziegler-Natta catalyst system. The polymerization mechanism of the rare earth catalyst may be similar to that of the general transition metal catalyst system not exactly.