Supported catalyst systems
Disclosed are methods of producing supported organic catalyst systems which find particular use in polymerization reactions. The methods comprise generally, the steps of (a) providing an organic catalyst solution comprising an organic catalyst dissolved in a solvent; (b) contacting the organic catalyst solution with a solid support material; and (c) removing the solvent from the support material by using one or more supercritical-like solvents.
1. A method of producing a supported metallocene catalyst system comprising the steps of:
(a) providing a metallocene catalyst solution comprising an hafnium metallocene catalyst dissolved in a supercritical-like solvent at a temperature of from about −10° C. to about 200° C.;
(b) contacting a support material with said metallocene catalyst solution; and
(c) removing substantially all of said supercritical-like solvent from said metallocene catalyst and said support material.
2. The method of claim 1 wherein said hafnium metallocene catalyst comprises halfnium (IV) compounds.
3. The method of claim 2 wherein said hafnium (IV) compound is dimethylbis(t-butylcyclopentadienyl) hafnium (IV).
4. The method of claim 1 wherein said supercritical-like solvent is a solvent in its supercritical state.
5. The method of claim 1 wherein said supercritical-like solvent comprises a liquid solvent in a subcritical state selected from the group consisting of methane, ethane, ethylene, propylene, trifluorochloromethane, difluoromethane, isomers of tetrafluoroethane, pentafluoroethane, isomers of trifluoroethane, isomers of pentafluoropropane, difluorochloromethane, isomers of tetrafluorochloroethane, carbon dioxide, ammonia, and mixtures of two or more thereof.
6. The method of claim 5 wherein said liquid solvent comprises liquid carbon dioxide.
7. The method of claim 1 wherein said providing step (a) comprises dissolving said metallocene catalyst in said supercritical-like solvent at a temperature of from about 30° C. to about 100° C.
8. The method of claim 1 wherein said providing step (a) comprises dissolving said metallocene catalyst in said supercritical-like solvent at a pressure of from about 25 psia to about 5,000 psia.
9. The method of claim 8 wherein said providing step (a) comprises dissolving said metallocene catalyst in said supercritical-like solvent at a pressure of from about 100 psia to about 3,500 psia.
10. The method of claim 1 , wherein said metallocene catalyst comprises a co-catalyst.
11. The method of claim 10 , wherein said co-catalyst is selected from the group consisting of tri-(n-butyl) ammonium tetrakis (pentafluorophenyl) boron, tris (pentafluorophenyl) borane, an alumoxane, methylalumoxane and mixtures thereof.
12. The method of claim 1 wherein said support material is selected from the group consisting of alumina, silica and silica treated with a halogenated organic compound.
13. The method of claim 12 wherein said support material comprises a plurality of particles.
14. A method of producing a supported metallocene catalyst system comprising the steps of:
(a) providing a metallocene catalyst solution comprising a transition metal metallocene catalyst dissolved in a supercritical-like solvent at a temperature of from about −10° C. to about 200° C., wherein said transition metal is selected from the group consisting of Group 4, Group 5, and Group 6 transition metals;
(b) contacting a support material with said metallocene catalyst solution; and
(c) removing substantially all of said supercritical-like solvent from said metallocene catalyst and said support material.
15. The method of claim 1 wherein said removing step (c) comprises converting said supercritical-like solvent to a gaseous state.
16. The method of claim 15 wherein said supercritical-like solvent is converted to a gaseous state by adjusting the temperature of said solvent.
17. The method of claim 15 wherein said supercritical-like solvent is converted to a gaseous state by adjusting the pressure of said solvent.
18. The method of claim 1 further comprising the steps of:
(d) providing a second metallocene catalyst solution comprising a second metallocene catalyst dissolved in a supercritical-like solvent;
(e) contacting said support material with said second metallocene catalyst solution; and
(f) removing substantially all of said supercritical-like solvent of said second solution from said second metallocene catalyst and said support material.
19. The method of claim 18 , wherein said metallocene catalyst solution and said second metallocene catalyst solution are contacted with said support material substantially simultaneously.
20. The method of claim 18 , wherein said solvent of said second solution is a selective solvent for said second metallocene catalyst.
21. A method for producing a supported metallocene catalyst system comprising the steps of:
(a) providing a metallocene catalyst solution comprising a metallocene catalyst selected from the group consisting of hafnium compounds and ferrocenes dissolved in a first solvent at a temperature of from about −10° C. to about 200° C.;
(b) contacting a support material with said catalyst solution; and
(c) removing substantially all of said first solvent by contacting said first solvent with a supercritical solvent and evaporating said supercritical solvent.
22. The method of claim 21 , wherein said first solvent is a liquid solvent.
23. The method of claim 21 further comprising the steps of:
(d) providing a second metallocene catalyst solution comprising a second metallocene catalyst dissolved in a second solvent at a temperature of from about −10° C. to about 200° C.;
(e) contacting said support material with said second metallocene catalyst solution; and
(f) removing substantially all of said second solvent by contacting said second solvent with a supercritical solvent and evaporating said supercritical solvent.
24. The method of claim 23 , wherein said metallocene catalyst solution and said second metallocene catalyst solution are contacted with said support material substantially simultaneously.
25. The method of claim 14 , wherein said transition metal is a group 4 metal.
26. A method of producing a supported metallocene catalyst system comprising the steps of:
(a) providing an organic catalyst solution comprising a metallocene catalyst dissolved in a solvent comprising a liquid hydrofluorocarbon solvent;
(b) contacting a support with said metallocene catalyst solution; and
(c) removing substantially all of said liquid hydrofluorocarbon solvent from said metallocene catalyst and said support material.
27. The method of claim 25 , wherein said transition metal is titanium.
28. The method of claim 26 , wherein said metallocene catalyst comprises a metallocene compound selected from the group consisting of zirconium metallocenes, hafnium metallocenes, and ferrocenes system.
29. The method of claim 28 , wherein said zirconium metallocene is selected from the group consisting of dichlorobis(n-butylcyclopentadienyl) zirconium (IV), dichlorobis(cyclopentadienyl) zirconium (IV) and mixtures thereof.
30. The method of claim 29 , wherein said hafnium metallocene compound is dimethylbis(t-butylcyclopentadienyl) hafnium (IV).
31. The method of claim 26 , wherein said metallocene catalyst comprises a co-catalyst system.
32. The method of claim 31 , wherein said co-catalyst is selected from the group consisting of tri-(n-butyl) ammonium tetra bis(pentafluorophenyl) boron, tris (pentafluorophenyl) borane, an alumoxane, methylalumoxane and mixtures thereof.
33. The method of claim 26 wherein said support is selected from the group consisting of alumina, silica and silica treated with a halogenated organic compound.
34. The method of claim 33 wherein said support comprises a plurality of particles.
35. The method of claim 33 wherein said support comprises a single unitary body.
36. The method of claim 26 wherein said hydrofluorocarbon solvent has a surface tension of about 22 dynes per centimeter or less.
37. The method of claim 26 wherein said hydrofluorocarbon contains at least about 65 weight percent fluorine.