Transition metal olefin polymerization processes
AssigneeExxon Chemical Patents Inc.
InventorsDonna J. Crowther, Richard A. Fisher, Jo Ann M. Canich, Gregory G. Hlatky, Howard W. Turner
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Abstract
This invention relates to processes using non-Group 4 transition metal compositions useful as olefin polymerization catalysts, wherein the transition metal is in a high oxidation state. The invention further relates to design of new ligand systems and methods of preparing and using the same. Compositions useful as catalyst precursors are neutral transition metal complexes comprising the unique ligand systems of the invention. The inventive compositions may be activated to a catalytic state by ion-exchange reagents or by Lewis acids.
Claims21
A process to produce polyolefins comprising contacting one or more olefins containing from 2 to 20 carbon atoms under polymerization conditions with a composition comprising a coordinatively unsaturated cationic transition metal complex having at least one reactive metal-ligand sigma bond, said cation stabilized by a low coordination number polyanionic ancillary ligand system and charge balanced with at least one compatible non-coordinating anion(s).
A process to produce polyolefins comprising contacting one or more olefins containing from 2 to 20 carbon atoms under polymerization conditions with a composition according to the formula:
- ( {(L.sub.3)A(L.sub.4)}.sup.-c M.sub.n (X)!.sup.+1).sub.q 'B.sup.-m !.sub.p
- wherein:
- M is group 5 or 6 transition metal in its highest oxidation state;
- n is the group number of the metal;
- L.sub.3 and L.sub.4 are the same or different substituted or unsubstituted anionic ancillary ligands covalently bonded to the metal;
- X is a uninegative ligand selected from hydride radicals, hydrocarbyl radicals, halogen-substituted hydrocarbyl radicals, halocarbyl radicals, hydrocarbyl-substituted organometalloid radicals;
- A is an optional bridging group bridging L.sub.3 and L.sub.4 ;
- c is an integer representing the charge on the ancillary ligand system {(L.sub.3)A(L.sub.4)};
- c+2=n
- 'B is a compatible non-coordinating anion of charge -m;
- p is the number of 'B anions;
- q is the number of +1 cations;
- and
- p times m=q.
A process to produce polyolefins comprising contacting one or more olefins containing from 2 to 20 carbon atoms under polymerization conditions with a composition according to the formula:
- {(L.sub.3)A(L.sub.4)}.sup.-c M.sub.n X.sub.2
- wherein:
- M is group 5 or 6 transition metal in its highest oxidation state;
- n is the group number of the metal;
- L.sub.3 and L.sub.4 are the same or different substituted or unsubstituted anionic ancillary ligands covalently bonded to the metal;
- X is a uninegative ligand selected from hydride radicals, hydrocarbyl radicals, halogen-substituted hydrocarbyl radicals, halocarbyl radicals, hydrocarbyl-substituted organometalloid radicals, halocarbyl-substituted organometalloid radicals, halides, alkoxides, amides or phosphides;
- A is an optional bridging group bridging L.sub.3 and L.sub.4 ;
- c is an integer representing the charge on the ancillary ligand system {(L.sub.3)A(L.sub.4)};
- and alumoxane.
Dependencies are inferred from the claim text.