Method for preparing non-metallocene catalysts
View Patent ↗A method of preparing supported catalysts useful for olefin polymerization is described. The catalysts comprise a Group 4 metal complex that incorporates a tridentate dianionic ligand. An activator mixture is first made from a boron compound having Lewis acidity and an excess of an alumoxane. The activator mixture is then combined with a support and the Group 4 metal complex to give a supported catalyst. The method provides an active, supported catalyst capable of making high-molecular-weight polyolefins.
1. A method of preparing a supported catalyst useful for polymerizing olefins, comprising: (a) combining a boron compound having Lewis acidity with excess alumoxane to produce an activator mixture; and (b) combining the activator mixture with a support and a dianionic, tridentate Group 4 metal complex to give the supported catalyst, wherein the complex comprises a 2-aryl-8-anilinoquinoline ligand.
2. The method of claim 1 wherein the boron compound is selected from the group consisting of boranes, boronic acids, borinic acids, and ionic borates.
3. The method of claim 1 wherein the alumoxane is methylalumoxane.
4. The method of claim 1 wherein the alumoxane and boron compound are used in amounts that provide an aluminum to boron (Al/B) molar ratio within the range of 2:1 to 1000:1.
5. The method of claim 4 wherein the Al/B molar ratio is within the range of 50:1 to 250:1.
6. The method of claim 1 wherein the support is silica.
7. The method of claim 6 wherein the silica has a surface area in the range of 10 to 1000 m 2 /g.
8. The method of claim 7 wherein the silica has a surface area in the range of 200 to 700 m 2 /g.
9. The method of claim 6 wherein the silica has a particle size in the range of 1 to 500 microns.
10. The method of claim 9 wherein the silica as a particle size in the range of 2 to 45 microns.
11. The method of claim 6 wherein the silica has a pore volume in the range of 0.05 to 4.0 mL/g.
12. The method of claim 6 wherein the silica has an average pore diameter in the range of 20 to 350 angstroms.
13. The method of claim 1 wherein the support is calcined at a temperature greater than 200° C.
14. The method of claim 1 wherein the activator mixture is first combined with the complex, followed by the support.
15. The method of claim 1 wherein the activator mixture is first combined with the support, followed by the complex.
16. The method of claim 1 wherein the 2-aryl-8-anilinoquinoline ligand has the following structure:
wherein M is a Group 4 transition metal, Ar is an aryl group, each X is independently selected from the group consisting of halide, amide, alkyl, and alkaryl, and further wherein any of the ring carbons is optionally substituted with an alkyl, aryl, halide, alkoxy, dialkylamino, or haloalkyl group, or any pair of adjacent ring carbons are joined to form a 5 to 7-membered carbocyclic or heterocyclic ring.
17. The method of claim 1 wherein the boron compound is lithium tetrakis(pentafluorophenyl)borate, sodium tetrakis(pentafluorophenyl)borate, anilinium tetrakis(pentafluorophenyl)borate, trityl tetrakis(pentafluorophenyl)borate, tris(pentafluorophenyl)borane, triphenylborane, tri-n-octylborane, bis(pentafluorophenyl)borinic acid, pentafluorophenylboronic acid.
18. The method of claim 1 wherein the alumoxane is ethylalumoxane.
19. The method of claim 1 wherein the alumoxane is isobutylalumoxane.
20. The method of claim 1 wherein the support is alumina, silica-alumina, magnesia, titania, zirconia, clay, zeolite, or some combination thereof.