Catalyst systems and methods for making and using the same are described. A method includes selecting a catalyst blend using a blend polydispersity index (bPDI) map. The polydispersity map is generated by generating a number of polymers for at least two catalysts. Each polymer is generated at a different hydrogen to ethylene ratio. At least one catalyst generates a higher molecular weight polymer and another catalyst generates a lower molecular weight polymer. A molecular weight for each polymer is measured. The relationship between the molecular weight of the polymers generated by each of the catalysts and the ratio of hydrogen to ethylene is determined. A family of bPDI curves for polymers that would be made using a number of ratios of a blend of the at least two catalysts for each of a number of ratios of hydrogen to ethylene. A ratio for the catalyst blend of the catalysts that generates a polymer having a bPDI that matches a polymer fabrication process is selected, and the product specific polyolefin is made using the catalyst blend.

Disclosed herein are catalyst compositions containing boron bridged, cyclopentadienyl-indenyl metallocene compounds with an alkenyl substituent. These catalyst compositions can be used for the polymerization of olefins. For example, ethylene homopolymers produced using these catalyst compositions can be characterized by a density less than 0.97 g/cm.sup.3 and a melt index greater than 50 g/10 min.

Improved preparation process for silica supported catalyst systems, which comprise a specific class of metallocene complexes in combination with a boron containing cocatalyst and an aluminoxane cocatalyst and use of the new, improved catalyst system.

New, improved silica supported catalyst system, which comprises a specific class of metallocene complexes in combination with a boron containing cocatalyst and an aluminoxane cocatalyst, its use for producing propylene homopolymers, propylene copolymers, especially with ethylene, as well as heterophasic propylene copolymers, preferably in a multistep process including a gas phase polymerization step.

Improved preparation process for supported catalyst systems, which comprise a specific class of metallocene complexes in combination with a boron containing cocatalyst and an aluminoxane cocatalyst and use of the new, improved catalyst system.

A specific class of metallocene complexes in combination with a boron containing cocatalyst and an aluminoxane cocatalyst, its use for producing propylene homopolymers, propylene copolymers, especially with ethylene, as well as heterophasic propylene copolymers, preferably in a multistep process including a gas phase polymerization step.

The alkylation of transition metal coordination catalyst complexes (such as metallocenes and/or post-metallocenes) in non-polar solvents with high conversion to the dialkylated transition metal coordination catalyst complex may be accomplished by reacting (a) a transition metal coordination catalyst complex comprising a transition metal linked to at least one an anionic donor ligand and at least one leaving group having a non-carbon atom directly linked to the transition metal, (b) an aluminum alkyl, and (c) a fluoride salt at 0 C. to 85 C. in a non-polar solvent to yield an alkylated transition metal coordination catalyst complex.

Improved preparation process for supported catalyst systems, which comprise a specific class of metallocene complexes in combination with a boron containing cocatalyst and an aluminoxane cocatalyst and use of the new, improved catalyst system.

Provided are a metallocene supported catalyst capable of greatly reducing generation of fine powder during preparation of olefin polymers while exhibiting excellent catalyst activity, and a method of preparing olefin polymers using the same.