US4056669A
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Polymerization process
Assignee: Imperial Chemical Industries Ltd
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Filing: 1973-07-09
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Granted: 1977-11-01
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Expires: 1993-07-09
Abstract
Abstract Polymerization of ethylene using a transition metal hydrocarbyl complex, especially zirconium tetrabenzyl, supported on alumina consisting of substantially spherical particles having diameters in the range 20-150 mu m. The particulate polymer produced by the process contains substantially no "fines" (i.e. particles <100 mu m diameter) and has improved pourability.
Inventors
- 👤 Denis George Harold Ballard
- 👤 Eric Jones
- 👤 John Christopher Padget
- 👤 Alexander Joseph Peter Pioli
- 👤 Peter Anthony Robinson
- 👤 John Walker
- 👤 Ronald John Wyatt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:55
CPC Classifications
C; C08; C08F; C08F10/00; Y; Y10; Y10S; Y10S526/00; Y10S526/908; Y10S526/909
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
151 words
A process for the polymerisation of ethylene in which the ethylene is contacted with a catalyst comprising a transition metal composition which is the product of reacting a transition metal complex of general formula MR m , where M is a metal of Group IVa, chromium or vanadium, R is selected from the group consisting of alkyl, alkenyl, and substituents of the formula --CH 2 Y, where Y is selected from the group consisting of aromatic groups, polyaromatic groups and groups of formula Z(R 1 ) 3 , where Z is silicon, germanium, tin or lead and each R 1 is hydrocarbon or hydrogen and m is an integer having a value equal to the valency of metal M, with particulate alumina which is free from adsorbed water, and which consists essentially of generally spherical particles, devoid of sharp edges, and has substantially no particles with diameters less than 20 μ.
Claim 2
Dependent Claim
151 words
A process for the polymerisation of ethylene in which the ethylene is contacted with a catalyst comprising a transition metal composition which is the product of reacting a transition metal complex of general formula MR m , where M is a metal of Group IVa, chromium or vanadium, R is selected from the group consisting of alkyl, alkenyl, and substituents of the formula --CH 2 Y, where Y is selected from the group consisting of aromatic groups, polyaromatic groups and groups of formula Z(R 1 ) 3 , where Z is silicon, germanium, tin or lead and each R 1 is hydrocarbon or hydrogen and m is an integer having a value equal to the valency of metal M, with particulate alumina which is free from adsorbed water, and which consists essentially of generally spherical particles, devoid of sharp edges, and has substantially no particles with diameters less than 20 μ.
Claim 3
Dependent Claim
18 words
A process as claimed in claim 1 in which the alumina particles are between 50 and 150 μ.
Claim 4
Dependent Claim
15 words
A process as claimed in claim 1 in which the alumina is a spray-dried alumina.
Claim 5
Dependent Claim
14 words
A process as claimed in claim 1 in which the metal used is zirconium.
Claim 6
Dependent Claim
17 words
A process as claimed in claim 4 in which the transition metal complex used is zirconium tetrabenzyl.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-31 | 1981-05-02 | 1981-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-31 | 1985-05-02 | 1985-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-31 | 1989-05-02 | 1989-11-01 | $7700.00 | Window Closed / Lapsed |