This invention relates to a catalyst compound for an olefin polymerization catalyst system represented by the formula: ##STR00001##
where each T is independently O, S, or N, each Q is independently C or Si; each R.sup.1, R.sup.2, and R.sup.3 is a substituted C.sub.1 to C.sub.40 hydrocarbyl group, a C.sub.1 to C.sub.40 hydrocarbyl group, or a substituted heteroatom, provided that the sum of the molecular volume of R.sup.1, R.sup.2, and R.sup.3 is greater than or equal to two times the molecular volume of an isopropyl group.

This invention relates to a catalyst compound for an olefin polymerization catalyst system represented by the formula: ##STR00001##
where each T is independently O, S, or N, each Q is independently C or Si; each R.sup.1, R.sup.2, and R.sup.3 is a substituted C.sub.1 to C.sub.40 hydrocarbyl group, a C.sub.1 to C.sub.40 hydrocarbyl group, or a substituted heteroatom, provided that the sum of the molecular volume of R.sup.1, R.sup.2, and R.sup.3 is greater than or equal to two times the molecular volume of an isopropyl group.

Disclosed herein are oligomerization processes in which ethylene and a catalyst system are first combined for a suitable residence time in an activation vessel, prior to introduction into a reaction zone to oligomerize ethylene to form a desired oligomer product, such as 1-hexene and/or 1-octene. Related oligomerization reaction systems that include the activation vessel also are disclosed. In these oligomerization processes and reaction systems, the catalyst system can be fully activated as it leaves the activation vessel and enters the reaction zone, thus providing greater catalyst utilization and less catalyst waste.

Disclosed herein are oligomerization processes in which ethylene and a catalyst system are first combined for a suitable residence time in an activation vessel, prior to introduction into a reaction zone to oligomerize ethylene to form a desired oligomer product, such as 1-hexene and/or 1-octene. Related oligomerization reaction systems that include the activation vessel also are disclosed. In these oligomerization processes and reaction systems, the catalyst system can be fully activated as it leaves the activation vessel and enters the reaction zone, thus providing greater catalyst utilization and less catalyst waste.

A method including contacting a chromium-based catalyst with a reducing agent in a solvent to lower an oxidation state of at least some chromium in the chromium-based catalyst to give a reduced chromium-based catalyst, drying the reduced chromium-based catalyst at a temperature, and adjusting the temperature to affect the flow index response of the reduced chromium-based catalyst.

A method including contacting a chromium-based catalyst with a reducing agent in a solvent to lower an oxidation state of at least some chromium in the chromium-based catalyst to give a reduced chromium-based catalyst, drying the reduced chromium-based catalyst at a temperature, and adjusting the temperature to affect the flow index response of the reduced chromium-based catalyst.

A method including contacting a chromium-based catalyst with a reducing agent in a solvent to lower an oxidation state of at least some chromium in the chromium-based catalyst to give a reduced chromium-based catalyst, drying the reduced chromium-based catalyst at a temperature, and adjusting the temperature to affect the flow index response of the reduced chromium-based catalyst.

The invention relates to tungsten oxo alkylidene complexes ligated with a tetraphenylphenoxy ligand and a neutral ligand such as a phosphine or a pyridine, and method of making the complexes. The complexes are useful as catalysts for performing a ring-opening metathesis polymerization of dicyclopentadiene to poly(dicyclopentadiene).

Disclosed herein are a chromium compound represented by Formula 1a or 1c and a catalyst system including the same, exhibiting superior catalytic activity in an olefin trimerization reaction:
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)][Formula 1a]
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)].sub.4.2H.sub.2O.[Formula 1c]

Disclosed herein are a chromium compound represented by Formula 1a or 1c and a catalyst system including the same, exhibiting superior catalytic activity in an olefin trimerization reaction:
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)][Formula 1a]
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)].sub.4.2H.sub.2O.[Formula 1c]