| 초록 |
Homogeneous non-metallocene catalytic systems for ethylene polymerization have drawn much attention, particularly late-transition metal derivatives. Nickel complexes were proved as good catalyst for ethylene oligomerization in SHOP process. With the same interest, we have developed a series of bimetallic Ni(II) complexes bearing push pull substituents, which serve as good catalysts for polymerization/oligomerization of ethylene. These nickel complexes were carefully examined with various catalytic conditions. The activity of the bimetallic complexes with different cocatalysts has been thoroughly investigated; out of which EAS showed high activity. In the presence of MAO, considerably good activities for ethylene oligomerization and polymerization were observed. UV-visible spectroscopic data have specified the important role of cocatalyst in the stabilization process of nickel based active species. The oligomers and polyethylene has been characterized by GC, NMR, GPC and DSC |
