| 초록 |
In 1995, Brookhart group of North Carolina University developed (α-diimine) nickel and (α-diimine) palladium catalysts that show high ethylene and α-olefin polymerization activity. In ethylene polymerization, the (α-diimine) nickel(II) catalysts produce high molecular weight polyethylene or low molecular weight oligomer depending on the bulkiness of aryl substituents. In this study, new (α-diimine) nickel(II) catalysts with controlled bulkiness of aryl substituents were synthesized. The polymers obtained with the catalysts were analyzed by 1H NMR,13C NMR, DSC, and GPC. Activity, branch density, branch distribution, and physical properties of the polyethylenes will be discussed.
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