Union Carbide Chemicals & Plastics Technology Corporation

Jody Michael Moffett

Mark Gregory Goode

Timothy R Lynn

Clark Curtis Williams

Robert Converse Brady, Iii

Kersten Anne Terry

Kersten Anne Erickson

William George Sheard

Preactivated unsupported catalyst compositions methods of using them are disclosed whereby the compositions have a concentration of preactivated catalyst of at least about 0.04 mmol of preactivated catalyst per liter of solution when using aliphatic or alicyclic hydrocarbon solvents, and a concentration of less than about 0.80 mmol/liter when using aromatic or halogen-substituted solvents. In the method, an unsupported catalyst precursor first is contacted with an activator, or co-catalyst, in a suitable reaction medium, and then the resulting mixture is contacted with additional solvent to form a preactivated unsupported olefin polymerization catalyst composition that can be fed to a gas phase polymerization reactor without plugging the catalyst injection nozzle. Combining the unsupported catalyst precursor, the co-catalyst and then adding additional solvent to provide such a composition prevents tube plugging, and provides a catalyst material that has high activity, avoids forming significant amounts of polymer agglomerates, and avoids reactor fouling.

Compositions and methods of using preactivated unsupported catalyst compositions having a given concentration

The present invention teaches the use of particular soluble metallocene catalyst to produce stereo-regular polymers in gas phase polymerizations wherein the catalysts are fed into a particle lean zone in the react. The metallocenes catalysts are bridged bis-(substituted indenyl) compounds.

Manufacture of stereoregular polymers

Methods of polymerizing olefins in the gas phase using unsupported catalyst compositions are disclosed. At least one olefin monomer is polymerized in a gas phase reactor in the presence of an unsupported liquid catalyst composition whereby the method reduces reactor fouling by maintaining the partial pressure of the primary olefin monomer that is polymerized below about 240 psi. in the reactor. The invention is particularly useful for, but is not limited to polymerizing propylene or copolymerizing propylene with olefins having two or more carbon atoms. The method described herein produces a polymer product having controlled, uniform particle size, narrow molecular weight distribution, high bulk density and stereoregularity, and prevents and/or inhibits reactor fouling during catalyst delivery and during polymerization.

Method of polymerizing olefins using unsupported catalyst compositions

The present invention teaches the use of particular soluble metallocene catalysts to produce stereoregular polymers in gas phase polymerizations wherein the catalysts are fed into a particular lean zone in the reactor. The metallocene catalysts are bridged bis(substituted indenyl) compounds.

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Charleston, WV, United States of America

Jody Michael Moffett