# US 2013/0158216 A1 · Use of Hydrogen and an Organozinc Compound for Polymerization and Polymer Property Control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0158216 A1 - Document ID: US20130158216A1 - Status: Published application - Kind: A1 - Application number: 13/329,404 - Filed: 2011-12-19 - Published: 2013-06-20 - Earliest claimed: 2011-12-19 - Assignees: Chevron Phillips Chemical Company LP - Inventors: Errun Ding; Qing Yang; Albert P. Masino; Youlu Yu; Lloyd W. Guatney; Jim B. Askew - Web page: https://patentgrep.com/patent/US20130158216A1 ## CPC - C08F 210/16: Copolymers of ethene with alpha-alkenes, e.g. EP rubbers - C08F 10/00: Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond - C08F 110/02: Ethene - C08F 2400/02: Control or adjustment of polymerization parameters - C08F 2410/07: Catalyst support treated by an anion, e.g. Cl-, F-, SO42- - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS ## Abstract Methods of controlling polymerization reactions using a synergistic amount of hydrogen and an organozinc compound are disclosed. The resulting polymers have lower molecular weights and higher melt flow indices. ## Claims ### Claim 1 A method of controlling a polymerization reaction in a polymerization reactor system, the method comprising: (i) introducing a transition metal-based catalyst composition, an olefin monomer, and optionally an olefin comonomer into a polymerization reactor within the polymerization reactor system, wherein the transition metal-based catalyst composition comprises (a) a transition metal compound; (b) an activator-support comprising a solid oxide treated with an electron-withdrawing anion; and (c) optionally, a co-catalyst; (ii) contacting the transition metal-based catalyst composition with the olefin monomer and the optional olefin comonomer under polymerization conditions to produce an olefin polymer; and (iii) introducing a synergistic amount of hydrogen and an organozinc compound into the polymerization reactor system to reduce a weight-average molecular weight (Mw) and/or to increase a melt index (MI) of the olefin polymer. ### Claim 2 (depends on 1) The method of claim 1, wherein the organozinc compound comprises a compound having the formula: Zn(X10)(X11); wherein: X10 is a C1 to C18 hydrocarbyl group; and X11 is H, a halide, or a C1 to C18 hydrocarbyl or C1 to C18 hydrocarboxy group. ### Claim 3 (depends on 1) The method of claim 1, wherein the organozinc compound comprises diethylzinc. ### Claim 4 (depends on 1) The method of claim 1, wherein the transition metal-based catalyst composition comprises chromium, vanadium, titanium, zirconium, hafnium, or a combination thereof. ### Claim at position 5 5-7. (canceled) ### Claim 8 (depends on 1) The method of claim 1, wherein: the activator-support comprises fluorided alumina, chlorided alumina, bromided alumina, sulfated alumina, fluorided silica-alumina, chlorided silica-alumina, bromided silica-alumina, sulfated silica-alumina, fluorided silica-zirconia, chlorided silica-zirconia, bromided silica-zirconia, sulfated silica-zirconia, fluorided silica-titania, fluorided silica-coated alumina, sulfated silica-coated alumina, phosphated silica-coated alumina, or any combination thereof; and the co-catalyst comprises an organoaluminum compound, the organoaluminum compound comprising trimethylaluminum, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, diisobutylaluminum hydride, diethylaluminum ethoxide, diethylaluminum chloride, or any combination thereof. ### Claim 9 (depends on 1) The method of claim 1, wherein the transition metal compound has the formula: Cr(XA)(X1)(X2)(L)n; wherein: XA is a substituted or unsubstituted cyclopentadienyl, indenyl, or fluorenyl group; X1 and X2 independently are a monoanionic ligand; and L is a neutral ligand, wherein n is 0, 1, or 2. ### Claim 10 (depends on 9) The method of claim 9, wherein: XA is a substituted cyclopentadienyl group; X1 and X2 independently are hydrogen, a halide, a C1 to C36 hydrocarbyl group, a C1 to C36 hydrocarbyloxy group, a C1 to C36 hydrocarbylaminyl group, a C1 to C36 hydrocarbylsilyl group, a C1 to C36 hydrocarbylaminylsilyl group, OBRA2, or OSO2RA, wherein RA is a C1 to C36 hydrocarbyl group; and L is an ether, a thioether, an amine, a nitrile, or a phosphine. ### Claim 11 (depends on 1) The method of claim 1, wherein the olefin monomer comprises a C2-C20 olefin. ### Claim 12 (depends on 1) The method of claim 1, wherein the olefin monomer comprises ethylene. ### Claim 13 (depends on 1) The method of claim 1, wherein the polymerization reactor system comprises a slurry reactor, a gas-phase reactor, a solution reactor, or a combination thereof. ### Claim 14 (depends on 1) The method of claim 1, wherein hydrogen is added to the polymerization reactor system at a hydrogen:olefin monomer molar ratio in a range from about 0.01:1 to about 0.2:1. ### Claim 15 (depends on 1) The method of claim 1, wherein the synergistic amount of hydrogen and the organozinc compound comprises a hydrogen:organozinc compound molar ratio in a range from about 100:1 to about 25,000:1. ### Claim 16 (depends on 1) The method of claim 1, wherein: a Mn of the olefin polymer is substantially unchanged; a ratio of Mw/Mn of the olefin polymer is reduced by at least 75%; the Mw of the olefin polymer is reduced by at least 75%; the Mw of the olefin polymer is reduced to less than about 200,000 g/mol; the MI of the olefin polymer is increased to at least about 1 g/10 min; or any combination thereof. ### Claim 19 An olefin polymerization process, the process comprising: contacting a transition metal-based catalyst composition with an olefin monomer and optionally an olefin comonomer under polymerization conditions, and in the presence of a synergistic amount of hydrogen and an organozinc compound, to produce an olefin polymer; wherein the transition metal-based catalyst composition comprises (a) a transition metal compound; (b) an activator-support comprising a solid oxide treated with an electron-withdrawing anion; and (c) optionally, a co-catalyst; and wherein: a Mw of the olefin polymer is less than about 200,000 g/mol; a MI of the olefin polymer is greater than about 1 g/10 min; or both. ### Claim 20 (depends on 19) The process of claim 19, wherein: the olefin monomer comprises ethylene; and the olefin comonomer comprises propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, styrene, or a mixture thereof. ### Claim 21 (depends on 19) The process of claim 19, wherein: a Mn of the olefin polymer is substantially unchanged; and a ratio of Mw/Mn of the olefin polymer is reduced by at least 75%. ### Claim 22 (depends on 19) The process of claim 19, wherein: the catalyst composition is contacted with ethylene and an olefin comonomer comprising 1-butene, 1-hexene, 1-octene, or a mixture thereof the Mw of the olefin polymer is reduced to within a range from about 60,000 to about 180,000 g/mol; and the MI of the olefin polymer is increased to within a range from about 1.5 to about 20 g/10 min. ### Claim 23 A method of controlling a polymerization reaction in a polymerization reactor system, the method comprising: (i) introducing a transition metal-based catalyst composition, an olefin monomer, and optionally an olefin comonomer into a polymerization reactor within the polymerization reactor system, wherein the transition metal-based catalyst composition comprises (a) a transition metal compound; (b) an activator-support comprising a solid oxide treated with an electron-withdrawing anion; and (c) optionally, a co-catalyst; (ii) contacting the transition metal-based catalyst composition with the olefin monomer and the optional olefin comonomer under polymerization conditions to produce an olefin polymer; and (iii) introducing a synergistic amount of hydrogen and an organozinc compound into the polymerization reactor system to reduce a weight-average molecular weight (Mw) and/or to increase a melt index (MI) of the olefin polymer; wherein: the synergistic amount of hydrogen and the organozinc compound comprises a hydrogen:organozinc compound molar ratio in a range from about 100:1 to about 25,000:1; and a Mn of the olefin polymer is substantially unchanged and/or a ratio of Mw/Mn of the olefin polymer is reduced by at least 75%. ### Claim 24 (depends on 23) The method of claim 23, wherein: the catalyst composition is contacted with ethylene and an olefin comonomer comprising 1-butene, 1-hexene, 1-octene, or a mixture thereof; the catalyst composition comprises an organoaluminum co-catalyst; and the activator-support comprises fluorided alumina, chlorided alumina, bromided alumina, sulfated alumina, fluorided silica-alumina, chlorided silica-alumina, bromided silica-alumina, sulfated silica-alumina, fluorided silica-zirconia, chlorided silica-zirconia, bromided silica-zirconia, sulfated silica-zirconia, fluorided silica-titania, fluorided silica-coated alumina, sulfated silica-coated alumina, phosphated silica-coated alumina, or any combination thereof. ### Claim 25 (depends on 24) The method of claim 24, wherein: the organozinc compound comprises diethylzinc; and the polymerization reactor system comprises a slurry reactor.