The synthesis and polymerization behavior of bimetallic pyridine diamide complexes containing transition metal (Ti, Zr)

Titanium and zirconium complexes with a pyridine diamide ligand, [2,6-(RNCH 2)(2)NC5H3](2-) (PDMP; R = 2,6-dimethylphenyl) have been synthesized and th eir catalytic behaviors investigated for ethylene polymerization. It was fo und that the zirconium complexes, [PDMP]ZrCl2 (7) and [PDMP][ZrCl3 x THF](2 ) (8), gave higher activities than the titanium complexes, [PDMP]TiCl2 (5) and [PDMP][TiCl3](2) (6). The bimetallic complexes (6, 8) gave higher activ ities than the corresponding monometallic complexes (5, 7). The titanium co mplexes gave polymers with higher molecular weight (M-w) than the zirconium complexes. The molecular weight distribution (M-w/M-n) of the polymers obt ained from the pyridine diamide complexes were much broader than that of th e normal metallocene catalysts. (C) 1999 John Wiley & Sons, Inc.