NdCl_3/MgCl_2 BISUPPORTED CATALYST FOR OLEFIN POLYMERIZATION

The NdCl_3/MgCl_2 bisupported catalyst was prepared by using NdCl_3 ,MgCl_2, (CH_3)_2(CH_2)_2 OH and TiCl_4. It is shown that the structure of bisupported catalyst was different from those of either NdCl_3 or MgCl_2 single supported catalyst. A peculiar type of kinetic curve for ethylene polymerization was found.

MgCl_2·6H_2O-BASED ZIRCONOCENE CATALYST FOR ETHYLENE POLYERIZATION

Several supported zirconocene catalysts were prepared by using MgCl_2·6H_2O as a precursor forproducing an active support. Such catalysts combined with methylaluminoxane (MAO) obtained by reactingMgCl_2·6H_2O with AlMe_3 show good activity for ethylene polymerization similar to that of anhydrousMgCl_2 supported zirconocene catalyst.

负载型Ziegler-Natta催化剂的研究进展——MgCl_(2)载体的活化及其对烯烃聚合的影响

以MgCl_(2)作为载体的负载型Ziegler-Natta催化剂是聚烯烃(特别是聚乙烯、聚丙烯)生产的重要催化剂,Ziegler-Natta催化剂的载体——活化MgCl_(2)的结构和形态影响了催化剂活性位点的空间分布及电子效应,进而决定了催化剂的催化特性(催化活性及立构选择性)。本文综述了负载型Ziegler-Natta催化剂中MgCl_(2)载体的不同活化方法对载体前驱体的形貌、结构、组成及制备的Ziegler-Natta预催化剂的颗粒形貌、结构、组成及催化烯烃聚合特性等的影响,结合不同方法制备的催化剂的工业应用,展望未来高性能聚烯烃催化剂的设计方向。