Method for preparing a supported metallocene-alumoxane catalyst for gas phase polymerization

Claim 2

A gas phase polymerization process for preparing polymers of ethylene, propylene, and copolymers of ethylene and alpha-olefins, respectively by I. polymerization of the monomers(s) in a gas phase polymerization reaction vessel in the presence of a supported metallocene-alumoxane catalyst obtained by: (a) adding undehydrated silica gel to a stirred solution of an aluminum trialkyl in an amount sufficient to provide a mole ratio of aluminum trialkyl to water of from about 3:1 to about 1:2 and allowing the mixture to react; (b) adding a metallocene of a Group 4b or 5b transition metal to the reacted mixture; (c) removing the solvent; (d) drying the solids to a free flowing powder, and II. recovering polymer product.

Claim 3

The process in accordance with claim 1, wherein said undehydrated silica gel has a water content of from about 6 to about 10 weight percent.

Claim 4

The process in accordance with claim 2, wherein the mole ratio of aluminum to transition metal in said metallocene is from about 1000:1 to about 1:1.

Claim 5

The process of claim 2, wherein said undehydrated silica gel has a water content of from about 7 to about 9 weight percent and the mole ratio of aluminum trialkyl to water is from about 1.2:1 to about 0.9:1.

Claim 6

The process of claim 4, wherein the mole ratio of aluminum to transition metal in said metallocene is from about 300:1 to about 10:1.

Claim 7

The process of claim 5, wherein the aluminum trialkyl is trimethyl aluminum or triethyl aluminum.

Claim 8

The process of claim 6, wherein said undehydrated silica gel has water content of from about 7.5 to about 8.5 weight percent.

Claim 9

The process of claim 7, wherein said undehydrated silica gel has a surface area of from about 200 to about 400 m 2 /g, a pore volume of from about 1 to about 2 cc/g and a particle size of from about 30μ to about 60μ.

Claim 10

The process of claim 8, wherein the mole ratio of aluminum to transition metal in said metallocene is from about 150:1 to about 30:1.

Claim 11

The process of claim 9, wherein said solids are dried at a temperature of from about 75° C. to about 85° C.

Claim 12

A gas phase polymerization process for preparing polymers of ethylene, propylene, and copolymers of ethylene and alpha-olefins, respectively by I. polymerization of the monomer(s) in a gas phase polymerization reaction vessel in the presence of a supported metallocene-alumoxane catalyst obtained by: (a) adding undehydrated silica gel to a stirred solution of an aluminum trialkyl in an amount sufficient to provide a mole ratio of aluminum trialkyl to water of from about 3:1 to about 1:2 and allowing the mixture to react; (b) adding to the reaction mixture a metallocene of the formula: (Cp) m MR n X q wherein Cp is a cyclopentadienyl ring, M is a Group 4b or 5b transition metal, R is a hydrocarbyl group of hydrocarboxy group having from: 1 to 20 carbon atoms, X is a halogen, and m is a whole number from 1 to 3, n is a whole number from 0 to 3, and q is a whole number from 0 to 3; (C 5 R' k ) g R" s (C 5 R' k )MQ 3-g , or R" s (C 5 R' k ) 2 MQ' wherein (C 5 R' k ) is a cyclopentadienyl or substituted cyclopentadienyl, each R' is the same or different and is hydrogen of a hydrocarbyl radical containing from 1 to 20 carbon atoms, a silicon-containing hydrocarbyl radical, or a hydrocarbyl radical wherein two carbon atoms are joined together to form a C 4 -C 6 ring, R" is C 1 -C 4 alkylene radical, a dialkyl germanium or silicone, or an alkyl phosphine or amine radical bridging two (C 5 R' k ) rings, Q is a hydrocarbyl radical having 1-20 carbon atoms, hydrocarboxy radical having 1-20 carbon atoms or halogen and can be the same or different, Q' is an alkylidene radical having from 1 to about 20 carbon atoms, s is 0 to 1, g is 0, 1 or 2; when g is 0, s is 0; k is 4 when s is 1 and k is 5 when s is 0 and M is as defined above; (c) removing the solvent; (d) drying the solids to a free flowing powder, and II. recovering polymer product.

Claim 13

A gas phase polymerization process for preparing polymers of ethylene, propylene, and copolymers of ethylene and alpha-olefins, respectively by I. polymerization of the monomer(s) in a gas phase polymerization reaction vessel in the presence of a supported metallocene-alumoxane catalyst obtained by: (a) adding undehydrated silica gel to a stirred solution of an aluminum trialkyl in an amount sufficient to provide a mole ratio of aluminum trialkyl to water of from about 3:1 to about 1:2 and allowing the mixture to react; (b) adding to the reaction mixture a metallocene of the formula: (Cp) m MR n X q wherein Cp is a cyclopentadienyl ring, M is a Group 4b or 5b transition metal, R is a hydrocarbyl group of hydrocarboxy group having from: 1 to 20 carbon atoms, X is a halogen, and m is a whole number from 1 to 3, n is a whole number from 0 to 3, and q is a whole number from 0 to 3; (C 5 R' k ) g R" s (C 5 R' k )MQ 3-g , or R" s (C 5 R' k ) 2 MQ' wherein (C 5 R' k ) is a cyclopentadienyl or substituted cyclopentadienyl, each R' is the same or different and is hydrogen of a hydrocarbyl radical containing from 1 to 20 carbon atoms, a silicon-containing hydrocarbyl radical, or a hydrocarbyl radical wherein two carbon atoms are joined together to form a C 4 -C 6 ring, R" is C 1 -C 4 alkylene radical, a dialkyl germanium or silicone, or an alkyl phosphine or amine radical bridging two (C 5 R' k ) rings, Q is a hydrocarbyl radical having 1-20 carbon atoms, hydrocarboxy radical having 1-20 carbon atoms or halogen and can be the same or different, Q' is an alkylidene radical having from 1 to about 20 carbon atoms, s is 0 to 1, g is 0, 1 or 2; when g is 0, s is 0; k is 4 when s is 1 and k is 5 when s is 0 and M is as defined above; (c) removing the solvent; (d) drying the solids to a free flowing powder, and II. recovering polymer product.

Claim 14

The process of claim 11, wherein said metallocene is zirconocene or titanocene.

Claim 15

The process of claim 12, wherein said zirconocene is selected from the group consisting of cyclopentadienyl zirconium trichloride pentamethylcyclopentadienyl zirconium trichloride; bis(cyclopentadienyl)zirconium diphenyl; bis(cyclopentadienyl)zirconium dichloride; alkyl substituted cyclopentadienes, and their dihalide complexes dialkyl, trialkyl, tetra-alkyl, and penta-alkyl cyclopentadienes, and their dihalide complexes; and silicone, phosphorus, and carbon bridged cyclopentadiene complexes.

Claim 16

The process of claim 12, wherein said titanocene is selected from the group consisting of monocyclopentadienyl titanocenes; bis(cyclopentadienyl) titanium diphenyl; carbenes represented by the formula Cp 2 Ti═CH 2 .Al(CH 3 ) 2 Cl, wherein Cp is a cyclopentadienyl or substituted cyclopentadienyl radical; substituted bis(Cp)Ti(IV) compounds and their dihalide complexes; dialkyl, trialkyl tetra-alkyl and penta-alkyl cyclopentadienyl titanium compounds and their dihalide complexes; and silicone, phosphine, amine or carbon bridged cyclopentadiene complexes, and their dihalide complexes.

Claim 17

The process of claim 12, wherein said undehydrated silica gel has a water content of from about 7 to about 9 weight percent and the mole ratio of aluminum trialkyl to water is from about 1.2:1 to about 0.9:1.

Claim 18

The process of claim 15, wherein the mole ratio of aluminum to transition metal in said metallocene is from about 300:1to about 10:1.

Claim 19

The process of claim 16, wherein the aluminum trialkyl is trimethyl aluminum or triethyl aluminum.

Claim 20

The process of claim 17, wherein said undehydrated silica gel has a water content of from about 7.5 to about 8.5 weight percent.

Claim 21

The process of claim 18, wherein said undehydrated silica gel has a surface area of from about 200 to about 400 m 2 /g, a pore volume of from about 1 to about 2 cc/g and a particle size of from about 30μ to about 60μ.

Claim 22

The process of claim 19, wherein the mole ratio of aluminum to transition metal in said metallocene is from about 150:1 to about 30:1.