| 초록 |
Recently, new late transition metal catalysts for the polymerization of olefins have attracted attention in academics and industry. In particular, aryl-substituted -diimine nickel(Ⅱ) complexes in combination with different cocatalysts show remarkably high activities in polymerization of ethylene. The high activities make the nickel(Ⅱ) catalysts desirable for applications in commercial polymerization. We reported here preparation of supported catalysts through use of aryl -diimine Ni(Ⅱ) complexes substituted with amino functionalities as reactive complexes and -cyclodextrin pretreated with trimethylaluminum as activated support material(Scheme 1). These tethered complexes were tested in slurry polymerization runs at 5 psig ethylene in toluene at temperatures between 30 and 70 ℃. The supported catalysts showed high activity for the ethylene polymerization in the presence of MAO and EAS. The resulting hyper-branched polyethylene has been characterized by NMR, GPC and DSC.
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