Novel Nickel Catalysts Containing Tetradentate Chelating Ligands for the Polymerization of Norbornene

2006

New nickel complexes containing novel tetradentate ligands, 4,5-substituted-1,2-bis(pyridine-2-carboxamide)-benzene ligands but lacking alkyl or halide ligands in the coordination sphere have been prepared. They were activated with MMAO (modified methylaluminoxane) to be proven as efficient catalysts for the polymerization of norbornene. Both electron-donating and -withdrawing substituents on the benzene ring and polar solvents enhance the catalytic activity for olefin polymerization. Improvement in thermal stability of the complexes was observed. Some of these complexes were crystallographically determined to have square planar geometry. A plausible mechanism involving dissociation of ligands is proposed. ऐ돀ࡾ�⨀堘�⨀�⨀돐࢑�⨀��⨀႑�⨀뤏덐ₑ�⨀렏頏䢑�⨀਀䢑�⨀墑�⨀؀က墑�⨀?塢Ѐက肑�⨀肑�⨀

Keywords:

Correction
Source
Cite
Save
Machine Reading By IdeaReader

28

References

17

Citations