Loading patent…
AssigneeUnion Carbide Chemicals & Plastics Technology Corporation
InventorsKersten Anne Terry, Jody Michael Moffett, William George Sheard
Estimating the term…
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.
A preactivated unsupported olefin polymerization catalyst composition comprising a preactivated unsupported olefin polymerization catalyst and a solvent, wherein the preactivated unsupported catalyst is prepared by contacting an unsupported olefin polymerization catalyst precursor, a co-catalyst, and the solvent for a period of time sufficient to form a preactivated unsupported olefin polymerization catalyst, wherein the solvent is selected from the group consisting of an aliphatic hydrocarbon solvent, an alicyclic hydrocarbon solvent, an aromatic solvent, a halogen-substituted solvent, and mixtures thereof, and wherein the concentration of the preactivated unsupported catalyst is within the range of from about 0.04 to about 0.1 mmol of preactivated unsupported catalyst per liter of solution when using an aliphatic or alicyclic hydrocarbon solvent, and the concentration is less than about 0.80 mmol/liter of preactivated unsupported catalyst when using an aromatic or halogen-substituted solvent.
A preactivated unsupported olefin polymerization catalyst composition comprising a preactivated unsupported olefin polymerization catalyst, and a solvent, wherein the preactivated unsupported catalyst is prepared by contacting an unsupported olefin polymerization catalyst precursor, a co-catalyst, and the solvent for more than about 40 minutes, wherein the solvent is selected from the group consisting of an aliphatic hydrocarbon solvent, an alicyclic hydrocarbon solvent, an aromatic solvent, a halogen-substituted solvent, and mixtures thereof, and wherein the concentration of the preactivated unsupported catalyst is within the range of from about 0.04 to about 0.1 mmol of preactivated unsupported catalyst per liter of solution when using an aliphatic or alicyclic hydrocarbon solvent, and the concentration is less than about 0.80 mmol/liter of preactivated unsupported catalyst when using an aromatic or halogen-substituted solvent.
Dependencies are inferred from the claim text.