Claims
- 1. A process for polymerizing olefins alone or in combination with one or more other olefins, said process comprising polymerizing in the presence of a supported catalyst system prepared by combining an inorganic oxide support material, a metallocene catalyst component, an activator and a surface modifier wherein the surface modifier is represented by the following formula: ##STR6## wherein R.sup.3 is hydrogen or a branched or linear alkyl group having 1 to 50 carbon atoms; and R.sup.1 is hydrogen or a branched or linear alkyl group having 1 to 50 carbon atoms which may contain a heteroatom selected from O, N, P or S; and R.sup.2 is (CH.sub.2).sub.x OH wherein x is an integer from 1 to 50; and wherein the weight percent of the surface modifier based on the total weight of the catalyst system is in the range of from 0.25 to 3.5 weight percent.
- 2. The process of claim 1 wherein the surface modifier is represented by the formula: ##STR7## where R.sup.1 is hydrogen or a linear or branched alkyl group of from 1 to 50 carbon atoms; R.sup.2 is (CH.sub.2).sub.x OH wherein x is an integer from 1 to 50.
- 3. The process of claim 1 wherein the surface modifier is selected from at least one of the group of compounds represented by the following chemical formula: C.sub.18 H.sub.37 N(CH.sub.2 CH.sub.2 O H).sub.2, and C.sub.12 H.sub.25 N(CH.sub.2 CH.sub.2 OH).sub.2.
- 4. The process of claim 1 wherein the surface modifier is a sorbitan mono-oleate compound.
- 5. The process of claim 1 wherein the surface modifier is a tertiary ethoxylated amine.
- 6. The process of claim 1 wherein the polymerization is conducted in a fluidized bed reactor, and further comprises:
- a) introducing a recycle stream into a reactor having fluidized bed, the recycle stream comprising monomer(s);
- b) introducing the supported catalyst system into the rector;
- c) withdrawing the recycle stream from the reactor;
- d) cooling the recycle stream;
- e) introducing into the recycle stream additional monomer(s) to replace the monomer(s) polymerized;
- f) reintroducing the recycle stream into the reactor; and
- g) withdrawing polymer product from the reactor.
- 7. The process of claim 6 wherein the recycle stream is cooled to form a liquid and a gas phase which is introduced into the reactor.
- 8. The process of claim 7 wherein the liquid and gas phase are introduced separately into the reactor.
- 9. The process of claim 7 wherein only the gas phase of the cooled recycle stream is introduced into the reactor.
- 10. The process of claim 6 wherein the monomer is ethylene.
- 11. The process of claim 6 wherein the liquid phase in the recycle stream is greater than about 2 to about 40 weight percent based on the total weight of the recycle stream.
- 12. The process of claim 6 wherein after step (c) another metallocene catalyst system comprising a metallocene catalyst component and activator is introduced into the reactor.
Parent Case Info
This is a divisional of application Ser. No. 08/501,897 filed Jul. 13, 1995.
US Referenced Citations (5)
Divisions (1)
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Number |
Date |
Country |
Parent |
501897 |
Jul 1995 |
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