US4368291A
Expired / Lapsed
US
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Process for the multi-stage polymerization of ethene
Assignee: VESTOLEN GmbH
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Filing: 1979-01-26
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Granted: 1983-01-11
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Expires: 1999-01-26
Abstract
Abstract In a low pressure process for polymerizing ethene using a Ziegler mixed catalyst comprising (a) a titanium compound, a vanadium compound or a mixture thereof and (b) an aluminum-organic compound or a mixture thereof, an improvement is provided wherein the process is carried out in multi-stages comprising: polymerizing, in a first polymerization stage, in the liquid phase in a dispersion medium of a C 3 - to C 6 -hydrocarbon, and polymerizing, in a last polymerization stage, in the gas phase.
Inventors
- 👤 Albert Frese
- 👤 Fritz Baxmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:54
CPC Classifications
C; C08; C08F; C08F10/00; C08F10/02; C08F210/00; C08F210/16; Y; Y10; Y10S; Y10S526/00; Y10S526/901
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
136 words
A low pressure process for polymerizing ethene, using a Ziegler mixed catalyst, comprising (a) a titanium compound, a vanadium compound or a mixture thereof, and (b) an organo-aluminum compound or a mixture thereof, in multi-stages, comprising: polymerizing ethene in a first polymerizing stage in the liquid phase in suspension using a dispersion medium of a C 3 - to C 6 -hydrocarbon up to a catalytic yield of at least 25 kg of polymer per gram of Ti or V catalyst or per gram of Ti catalyst and V catalyst if both are present; polymerizing, in a last polymerization stage, in the gas phase; and optionally, polymerizing in intermediate stages; all liquid stages preceding the gas stages; wherein, the polymer-containing dispersion medium resulting from the last liquid stage is directly introduced into the first gas stage.
Claim 2
Dependent Claim
136 words
A low pressure process for polymerizing ethene, using a Ziegler mixed catalyst, comprising (a) a titanium compound, a vanadium compound or a mixture thereof, and (b) an organo-aluminum compound or a mixture thereof, in multi-stages, comprising: polymerizing ethene in a first polymerizing stage in the liquid phase in suspension using a dispersion medium of a C 3 - to C 6 -hydrocarbon up to a catalytic yield of at least 25 kg of polymer per gram of Ti or V catalyst or per gram of Ti catalyst and V catalyst if both are present; polymerizing, in a last polymerization stage, in the gas phase; and optionally, polymerizing in intermediate stages; all liquid stages preceding the gas stages; wherein, the polymer-containing dispersion medium resulting from the last liquid stage is directly introduced into the first gas stage.
Claim 3
Dependent Claim
19 words
The process of claim 1, which further comprises polymerizing in additional stages between the first and last polymerization stages.
Claim 4
Dependent Claim
16 words
The process of claim 1, wherein ethene is polymerized in all stages whereby homopolyethene is produced.
Claim 5
Dependent Claim
27 words
The process of claim 1, wherein in addition to ethene, another olefin monomer is polymerized, whereby a random copolymer or a block copolymer of ethene is prepared.
Claim 6
Dependent Claim
48 words
The process of claim 1, wherein, in the non-final stages, the heat of polymerization is removed by circulatory gas cooling, evaporative cooling and/or jacket cooling and in the last polymerization stage the residual dispersion medium is evaporated with the aid of the heat of polymerization and is removed.
Claim 7
Dependent Claim
32 words
The process of claim 1 or 5, wherein, in the initial polymerization stages, the polymerization is carried out in stirrer kettles, and in the intermediate polymerization stages, is carried out in mixers.
Claim 8
Dependent Claim
19 words
The process of claim 5 or 6, wherein the last polymerization stage is carried out in a fluidized bed.
Claim 9
Dependent Claim
15 words
The process of claim 1, wherein all the catalyst is added in the first stage.
Claim 10
Dependent Claim
94 words
A process for preparing a homopolymer of ethene or a copolymer of ethene with another olefin using a Ziegler mixed catalyst, comprising (a) a titanium compound, a vanadium compound or a mixture thereof, and (b) an organo-aluminum compound or a mixture thereof, which comprises polymerizing in the gas phase using as a starting material the polymer-containing dispersion medium resulting from a liquid phase suspension polymerization of a portion of the desired final homo- or copolymer carried out in a C 3-6 hydrocarbon medium, the solids content of the polymer-containing dispersion medium being 300-700 g/l.
Claim 11
Dependent Claim
94 words
A process for preparing a homopolymer of ethene or a copolymer of ethene with another olefin using a Ziegler mixed catalyst, comprising (a) a titanium compound, a vanadium compound or a mixture thereof, and (b) an organo-aluminum compound or a mixture thereof, which comprises polymerizing in the gas phase using as a starting material the polymer-containing dispersion medium resulting from a liquid phase suspension polymerization of a portion of the desired final homo- or copolymer carried out in a C 3-6 hydrocarbon medium, the solids content of the polymer-containing dispersion medium being 300-700 g/l.
Claim 12
Dependent Claim
62 words
The process of claim 9, which comprises polymerizing in multi-stages; in the initial ones, by polymerizing in the liquid phase in suspension using a dispersion medium of a C 3-6 hydrocarbon, and in the remaining ones by polymerizing in the gas phase, wherein in the first gas stage the starting material is the polymer-containing dispersion medium resulting from the last liquid stage.
Claim 13
Dependent Claim
31 words
The process of claim 9, wherein, in the liquid stages, the polymerization is carried out in a stirred kettle and, in the gas stages, is carried out in a fluidized bed.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-10 | 1986-07-12 | 1987-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-10 | 1990-07-12 | 1991-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-10 | 1994-07-12 | 1995-01-11 | $7700.00 | Window Closed / Lapsed |