Cofeeds of electron donating and electron withdrawing reagents to control MW in olefin polymerization using supported metallocene catalyst

- Mobil Oil Coporation

In gas phase polymerizations and copolymerizations of ethylene, reagents or cofeeds control the molecular weight, expressed as MI (wherein MI is measured according to ASTM D-1238 Condition E), of the resin product. Use of isopentane and electron donating compounds decrease MI; whereas, electron withdrawing compounds increase MI.

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Claims

1. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55 to 115 degrees C., in a fluid bed gas phase process conducted at less than 1000 psi, which produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than 1000 psi, at a temperature which is in a range of from 55 degrees C. as a lower limit and a maximum limit of 115 degrees C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in a range of 55 degrees C. to about 95 degrees C.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount of aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al:(transition metal) mole ratio (elemental basis) ranges from 25 to 10000;
(f) introducing to the fluidized bed gas phase reactor a compound selected from the group consisting of isopentane and an electron donating compound;
(g) recovering polymerization product with MI of less than 4, having a settled bulk density in the range of 22 to 36 lb/ft.sup.3 and a specific density of less than 0.94 g/cc.

2. The process of claim 1, wherein the constant polymerization temperature is in the range of 65 to 85 degrees C.

3. The process of claim 1, wherein the constant polymerization temperature is in the range of 75 to 80 degrees C.

4. The process of claim 1, wherein the catalyst is in the form of particles,

wherein said particles have a particle size in the range of 1 to 500 microns
wherein said particles comprise silica, a transition metal and aluminum, wherein the ratio of aluminum to transition metal ranges from about 70 to 350;
wherein said silica is amorphous and porous and has a pore volume of 0.1 to 5 cc/gm; wherein said silica has a concentration of hydroxyl groups wherein the concentration of hydroxyl groups is in the range of 0.01 to 2.5 mmole per gram of silica;
wherein said silica is contacted with a volume of a mixture comprising a metallocene and an alumoxane,
wherein said volume of said mixture is no greater than the total pore volume of said dehydrated silica,
wherein said metallocene has a formula, Cp.sub.m MA.sub.n B.sub.p,
wherein
Cp is a substituted cyclopentadienyl group;
m is 1 or 2;
M is zirconium or hafnium; and
each of A and B is selected from the group consisting of a halogen atom, a hydrogen atom, an alkoxyl and an alkyl group, providing that m+n+p is equal to the valence of the metal M;
wherein said alumoxane has a formula (a) or (b) wherein (a) is R--(Al(R)--O).sub.n --AlR.sub.2 for oligomeric, linear alumoxanes and (b) is (--Al(R)--O--).sub.m for oligomeric cyclic alumoxane wherein n is 1-40, m is 3-40, and R comprises a C.sub.1 -C.sub.8 alkyl group;
wherein said contacted silica is an activated catalyst.

5. The process of claim 4, wherein the metallocene is selected from the group consisting of bis(n-butylcyclopentadienyl)metal dihalides, bis(n-butylcyclopentadienyl)metal hydridohalides, bis(n-butylcyclopentadienyl)metal monoalkyl monohalides, bis(n-butylcyclopentadienyl)metal dialkyls and bis(indenyl)metal dihalides.

6. The process of claim 5, wherein the metallocene is selected from the group consisting of bis(n-butylcyclopentadienyl)metal dihalides, bis(n-butylcyclopentadienyl)metal hydridohalides, bis(n-butylcyclopentadienyl)metal monoalkyl monohalides, bis(n-butylcyclopentadienyl)metal dialkyls and bis(indenyl)metal dihalides.

7. The process of claim 4, wherein the constant polymerization temperature is in the range of 75 to 85 degrees C.

8. The process of claim 7, wherein the constant polymerization temperature is in the range of 75 to 80 degrees C.

9. The process of claim 1, wherein the electron donating compound is used in an amount ranging from 0.01 to 500 ppm molar ratio to ethylene.

10. The process of claim 9 wherein the electron donating compound is selected from the group consisting of oxygen, carbon monoxide and carbon dioxide.

11. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55.degree. to 115.degree. C., in a fluid bed gas phase process conducted at less than 1000 psi, produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than about 1000 psi, at a temperature which is in a range of from 55.degree. C. as a lower limit and a maximum limit of 115.degree. C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in the range of 55.degree. C. to 95.degree.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount of aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al:(transition metal) mole ratio (elemental basis) ranges from 25 to 10000;
(f) introducing an electron donor to the fluidized bed gas phase reactor,
(g) recovering polymerization product having a settled bulk density in the range of 22 to 36 lb/ft3 and a specific density of less than 0.94 g/cc.

12. The process of claim 11, wherein the constant polymerization temperature is in the range of 65.degree. to 90.degree. C.

13. The process of claim 11, wherein the constant polymerization temperature is in the range of 75.degree. to 80.degree. C.

14. The process of claim 11, wherein the catalyst is in the form of particles,

wherein said particles have a particle size in the range of 1 to 500 microns
wherein said particles comprise silica, a transition metal and aluminum, wherein the molar ratio of aluminum to transition metal ranges from 70 to 350;
wherein said silica is amorphous and porous and has a pore volume of 0.1 to 5 cc/gm; wherein said silica has a concentration of silanol groups wherein the concentration of silanol groups is in the range of 0.01 to 2.5 mmole per gram of silica;
wherein said silica is contacted with a volume of a mixture comprising a metallocene and an alumoxane,
wherein said volume of said mixture is no greater than the total pore volume of said dehydrated silica,
wherein said metallocene has a formula, Cp.sub.m MA.sub.n B.sub.p,
wherein
Cp is a substituted cyclopentadienyl group;
m is 1 or 2;
M is zirconium or hafnium; and
each of A and B is selected from the group consisting of a halogen atom, a hydrogen atom, an alkoxyl group and an alkyl group, providing that m+n+p is equal to the valence of the metal M;
wherein said alumoxane has a formula (a) or (b) wherein (a) is R--(Al(R)--O).sub.n --AlR.sub.2 for oligomeric, linear alumoxanes and (b) is (--Al(R)--O--).sub.m for oligomeric cyclic alumoxane wherein n is 1-40, m is 3-40, and R comprises a C.sub.1 -C.sub.8 alkyl group;
wherein said contacted silica is an activated catalyst.

15. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55.degree. to 115.degree. C., in a fluid bed gas phase process conducted at less than 1000 psi, produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than 1000 psi, at a temperature which is in a range of from 55.degree. C. as a lower limit and a maximum limit of 115.degree. C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in the range of 55.degree. C. to 95.degree. C.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount of aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al:(transition metal) mole ratio (elemental basis) ranges from 25 to 10000;
(f) introducing isopentane to the fluidized bed gas phase reactor,
(g) recovering polymerization product having a settled bulk density in the range of 22 to 36 lb/ft.sup.3 and a MI value of less than 5.

16. The process of claim 15, wherein the constant polymerization temperature is in the range of 65 to 85 degrees C.

17. The process of claim 16, wherein the constant polymerization temperature is in the range of 75 to 80 degrees C.

18. The process of claim 15, wherein isopentane is used in an amount ranging from 2 to 80 psi.

19. The process of claim 15, wherein the isopentane is cofed with an electron donating compound which is selected from the group consisting of oxygen, carbon monoxide and carbon dioxide.

20. The process of claim 19, wherein the constant polymerization temperature is in the range of about 75 to about 85 degrees C.

21. The process of claim 15, wherein the constant polymerization temperature is in the range of 65.degree. to 90.degree. C.

22. The process of claim 15, wherein the constant polymerization temperature is in the range of 75.degree. to 80.degree. C.

23. The process of claim 15, wherein the catalyst is in the form of particles,

wherein said particles have a particle size in the range of 1 to 500 microns;
wherein said particles comprise silica, a transition metal and aluminum, wherein the ratio of aluminum to transition metal ranges from 70 to 350;
wherein said silica is amorphous and porous and has a pore volume of 0.1 to 5 cc/gm; wherein said silica has a concentration of silanol groups wherein the concentration of silanol groups is in the range of 0.01 to 2.5 mmole per gram of silica;
wherein said silica is contacted with a volume of a mixture comprising a metallocene and an alumoxane,
wherein said volume of said mixture is no greater than the total pore volume of said dehydrated silica,
wherein said metallocene has a formula, Cp.sub.m MA.sub.n B.sub.p,
wherein
Cp is a substituted cyclopentadienyl group;
m is 1 or 2;
M is zirconium or hafnium; and
each of A and B is selected from the group consisting of a halogen atom, a hydrogen atom, an alkoxyl group and an alkyl group, providing that m+n+p is equal to the valence of the metal M;
wherein said alumoxane has a formula (a) or (b) wherein (a) is R--(Al(R)--O).sub.n --AlR.sub.2 for oligomeric, linear alumoxanes and (b) is (--Al(R)--O--).sub.m for oligomeric cyclic alumoxane wherein n is 1-40, m is 3-40, and R comprises a C.sub.1 -C.sub.8 alkyl group;
wherein said contacted silica is an activated catalyst.

24. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55.degree. to 115.degree. C., in a fluid bed gas phase process conducted at less than 1000 psi, produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than about 1000 psi, at a temperature which is in a range of from about 55.degree. C. as a lower limit and a maximum limit of 115.degree. C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in the range of about 55.degree. C. to 95.degree. C.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount of aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al:(transition metal) mole ratio (elemental basis) ranges from 25 to 10000;
(f) introducing carbon dioxide to the fluidized bed gas phase reactor,
(g) recovering polymerization product having a settled bulk density in the range of 22 to 36 lb/ft.sup.3 and a specific density of less than about 0.94 g/cc.

25. The process of claim 24, wherein the constant polymerization temperature is in the range of 65.degree. to 90.degree. C.

26. The process of claim 24, wherein the constant polymerization temperature is in the range of 75.degree. to 80.degree. C.

27. The process of claim 24, wherein the catalyst is in the form of particles,

wherein said particles have a particle size in the range of 1 to 500 microns
wherein said particles comprise silica, a transition metal and aluminum, wherein the ratio of aluminum to transition metal ranges from 70 to 350;
wherein said silica is amorphous and porous and has a pore volume of 0.1 to 5 cc/gm; wherein said silica has a concentration of silanol groups wherein the concentration of silanol groups is in the range of 0.01 to 2.5 mmole per gram of silica;
wherein said silica is contacted with a volume of a mixture comprising a metallocene and an alumoxane,
wherein said volume of said mixture is no greater than the total pore volume of said dehydrated silica, wherein said metallocene has a formula, Cp.sub.m MA.sub.n B.sub.p,
wherein
Cp is a substituted cyclopentadienyl group;
m is 1 or 2;
M is zirconium or hafnium; and
each of A and B is selected from the group consisting of a halogen atom, a hydrogen atom, an alkoxyl group and an alkyl group, providing that m+n+p is equal to the valence of the metal M;
wherein said alumoxane has a formula (a) or (b) wherein (a) is R--(Al(R)--O).sub.n --AlR.sub.2 for oligomeric, linear alumoxanes and (b) is (--Al(R)--O--).sub.m for oligomeric cyclic alumoxane wherein n is 1-40, m is 3-40, and R comprises a C.sub.1 -C.sub.8 alkyl group;
wherein said contacted silica is an activated catalyst.

28. The process of claim 15, wherein the isopentane is introduced together with at least one compound selected from the group consisting of oxygen, carbon monoxide and carbon dioxide.

29. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55.degree. to 115.degree. C., in a fluid bed gas phase process conducted at less than 1000 psi, produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than 1000 psi, at a temperature which is in a range of from 55.degree. C. as a lower limit and a maximum limit of 115.degree. C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in the range of about 55.degree. C. to 95.degree.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al: (transition metal) ratio (elemental basis) ranges from 25 to 10000;
(f) introducing carbon monoxide to the fluidized bed gas phase reactor,
(g) recovering polymerization product having a settled bulk density in the range of 22 to 36 lb/ft3 and a MI value of less than 5.

30. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55.degree. to 115.degree. C., in a fluid bed gas phase process conducted at less than 1000 psi, produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than 1000 psi, at a temperature which is in a range of from 55.degree. C. as a lower limit and a maximum limit of 115.degree. C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in the range of about 55.degree. C. to 95.degree. C.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount of aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al:(transition metal) mole ratio (elemental basis) ranges from 25 to 10000;
(f) introducing oxygen to the fluidized bed gas phase reactor,
(g) recovering polymerization product having a settled bulk density in the range of 22 to 36 lb/ft.sup.3 and a MI value of less than 5.

31. In a process for the polymerization of ethylene or the copolymerization of ethylene with an alpha olefin of 3 to 10 carbon atoms, at temperatures ranging from 55.degree. to 115.degree. C., in a fluid bed gas phase process conducted at less than 1000 psi, produces resin having a MI (g/10 min.) value in the range of 0.0001 to 500, (wherein MI is measured according to ASTM D-1238 Condition E), wherein the process comprises

(a) fluidizing a catalyst, in a fluid bed gas phase reactor,
(b) contacting said catalyst with a feed selected from the group consisting of (1) ethylene, (2) ethylene admixed with hydrogen, (3) ethylene admixed with an alpha olefin of 3 to 10 carbon atoms, and (4) ethylene admixed with hydrogen and an alpha olefin of 3 to 10 carbon atoms;
(c) maintaining a polymerization pressure of less than 1000 psi, at a temperature which is in a range of from 55.degree. C. as a lower limit and a maximum limit of 115.degree. C.;
wherein the improvement comprises
(d) maintaining a constant polymerization temperature which is in the range of 55.degree. C. to 95.degree.;
(e) providing an activated particulate metallocene catalyst, and fluidizing the activated particulate metallocene catalyst,
wherein the catalyst comprises a porous, amorphous support which is silica, alumina or silica/alumina
wherein the catalyst comprises said support, a transition metal and aluminum, wherein the amount of transition metal (elemental basis) ranges from 0.001 to 10 weight percent and the amount of aluminum (elemental basis) ranges from 1 to 40 weight percent, wherein the Al: (transition metal) mole ratio (elemental basis) ranges from 25 to 10000;
(f) introducing an electron donor to the fluidized bed gas phase reactor,
(g) recovering polymerization product having a settled bulk density in the range of 22 to 36 lb/ft.sup.3 and a MI value of less than 5.
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Patent History
Patent number: 5883203
Type: Grant
Filed: Oct 10, 1997
Date of Patent: Mar 16, 1999
Assignee: Mobil Oil Coporation
Inventors: Subrahmanyam Cheruvu (Robbinsville, NJ), Frederick Y. Lo (Edison, NJ), Shih-May Christine Ong (Warren, NJ)
Primary Examiner: Fred Teskin
Attorneys: Lori F. Cuomo, Dennis P. Santini
Application Number: 8/947,674