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Tetra(neophyl) zirconium

Assignee: EIDP Inc
•
Filing: 1975-07-30
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Granted: 1977-04-12
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Expires: 1995-07-30
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Abstract

Abstract There are disclosed olefin polymerization catalysts based on tetra(neophyl) zirconium and its reaction products with surface-hydroxylated oxides of metals of Groups II(a), III(a), IV(a) and IV(b) of the Periodic Table of the Elements, processes for their preparation, and processes for the polymerization of olefinic monomers employing such catalysts. Neophyl zirconium aluminate supported on alumina is disclosed as the preferred, most active catalyst. The polyolefins produced are linear high polymers of high crystallinity such as polyethylene and isotactic polypropylene. Diolefins are converted into rubber by use of the process employing the catalyst. Ethylene-propylene copolymer rubbers can also be produced by use of the catalysts.

Inventors

  • 👤 Robert Alton Setterquist

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 16:12
CPC Classifications
C; C07; C07F; C07F5/00; C07F5/06; C07F5/069; C08; C08F; C08F10/00

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 1 words
Tetra(neophyl)zirconium.
Claim 2
Dependent Claim 1 words
Tetra(neophyl)zirconium.

References Cited (Backward Citations)

US3813423A Cited
US3763197A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-04-11 1980-10-11 1981-04-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-04-11 1984-10-11 1985-04-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-04-11 1988-10-11 1989-04-12 $7700.00 Window Closed / Lapsed

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