Polymerization process
AssigneeExxonMobil Chemical Patents Inc.
InventorsRobert O. Hagerty, Randall B. Laird, Michael A. Risch, Pradeep P. Shirodkar, Peijun Jiang
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Abstract
This invention is directed to processes of making polymer in the presence of a fluorinated hydrocarbon and recovering the polymer. The processes provided enable polymerization processes to be practiced with minimal fouling in the reaction system, and allows for the recovery of the fluorinated hydrocarbon and other hydrocarbons such as hydrocarbons for re-use in the process or hydrocarbon by-products from the polymerization process. The invention is particularly beneficial in the production of propylene-ethylene based copolymers using Ziegler-Natta catalyst systems.
Claims52
A process for producing an elastomeric polypropylene copolymer, comprising:
- mixing together a diluent containing more than 10 weight percent of a fluorinated hydrocarbon based on the total weight of the diluent, a supported Ziegler-Natta catalyst system, and an olefin feed containing at least 25 weight % propylene and greater than 10 weight % ethylene, based on total weight of the feed, to provide a slurry;
- and
- forming an elastomeric polypropylene copolymer having a melting point of greater than or equal to 10° C., and wherein the diluent comprises a mixture of at least one saturated hydrocarbon and at least one fluorinated hydrocarbon wherein the mixture has a density in the range of from 0.2 g/cc less than to 0.2 g/cc greater than the density of the polymer.
A process for producing copolymer comprising:
- mixing together a diluent containing at least one fluorinated hydrocarbon, a supported Ziegler-Natta catalyst system, and an olefin feed containing at least 25 weight % propylene and greater than 10 weight % ethylene, based on total weight of the feed, to form a slurry containing copolymer;
- and
- recovering the copolymer from the slurry, wherein the copolymer has a melting point of greater than or equal to 10° C., and wherein the diluent comprises a mixture of at least one saturated hydrocarbon and at least one fluorinated hydrocarbon wherein the mixture has a density in the range of from 0.2 g/cc less than to 0.2 g/cc greater than the density of the polymer.
Dependencies are inferred from the claim text.