Catalyst compositions and methods useful in polymerization processes utilizing
at least two metal compounds are disclosed. At least one of the metal compounds
is a Group 15 containing metal compound and the other metal compound is preferably
a bulky ligand metallocene-type catalyst. The invention also discloses a new polyolefin,
generally polyethylene, particularly a multimodal polymer and more specifically,
a bimodal polymer, and its use in various end-use applications such as film, molding
and pipe. The Group 15 containing metal compound is represented in one embodiment
by the formulae:
##STR1##
- wherein M is a Group 4, 5, or 6 metal;
- each X is independently a leaving group;
- y is 0 or 1;
- n is the oxidation state of M;
- m is the formal change of the ligand comprising the YZL or YZL groups;
- L is a Group 15 or 16 element;
- L is a Group 15 or 16 element or Group 14 containing group;
- Y is a Group 15 element;
- Z is a Group 15 element;
- and the other groups are as defined herein.
