| 초록 |
In order to be applied in the conventional gas phase or slurry reactors, homogeneous catalysts have to be heterogenized. As a different heterogenization strategy we have developed a series of spherical SiO2 supported α-diimine Ni and bisiminopyridyl Fe catalysts for ethylene polymerization that keep the advantages of homogeneous catalysts and improve the morphology of polymer. All catalysts were highly active towards ethylene polymerization exceeding activities 107 g-PE/mol-Ni h bar even at atmospheric conditions when activated with methyl aluminoxane (MAO) and common alkyl aluminums such as ethyl aluminium sesquichloride (EAS) and diethylaluminium dichloride (DEAC). No obvious catalyst fragmentation or leaching of the catalyst components from the support are observed during polymerization, so that the polymer morphology is tunable from uniform sphere to fiber, depending upon the catalytic activity, metal loading, and effective selection of cocatalysts. |
