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自本世纪五十年代,K·齐格勒和 G·纳塔用烷基铝-氧化钛为催化剂创造性地开拓了-α烯烃的立体定向聚合以后,迅速开展了对齐格勒-纳塔催化剂的研究工作。齐格勒和纳塔所用的催化剂一般是由周期表中Ⅰ～Ⅱ族的金属烷基化合物和Ⅳ～Ⅷ族过渡金属化合物所组成。前者如 LiR、AlR_3、AlR_2Cl、MgR_2、BeR_2、ZnR_2,若与 TiCl_4、TiCl_3,VCl_3等过渡金属卤化物,则构成不溶性双金属络合物;但若与(π-C_5H_5)_2TiCl_2、VOCl_3、VO(OR)_3等过渡金属化合物就构成可溶性的催化剂。近年来还发现,某些稀土金属,如钍、钋、铈等
Since the 1950s, K. Ziegler and G Natta have pioneered the stereospecific polymerization of -α olefins with aluminum alkyl-titania as a catalyst and have rapidly developed the Ziegler-Natta catalyst research work. The catalysts used for Ziegler and Natta generally consist of Group I-II metal alkyl compounds and Group IV-VIII transition metal compounds of the Periodic Table. The former such as LiR, AlR_3, AlR_2Cl, MgR_2, BeR_2, ZnR_2, and TiCl_4, TiCl_3, VCl_3 and other transition metal halides constitute insoluble bimetallic complexes; but if and π-C_5H_5 _2TiCl_2, VOCl_3, VO OR) _3 and other transition metal compounds constitute a soluble catalyst. In recent years also found that some rare earth metals, such as thorium, thulium, cerium and so on