US4190614A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the production of low density copolymers of ethylene
Assignee: Mitsui Toatsu Chemicals Inc
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Filing: 1977-04-04
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Granted: 1980-02-26
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Expires: 1997-04-04
Abstract
Abstract In producing a low density polyethylene by a slurry copolymerization of ethylene and an alpha -olefin with use of a catalyst consisting of a magnesium compound-supported titanium and/or vanadium compound and an organoaluminum compound, a certain amount of ethylene is subject to a pre-polymerization in the presence of said catalyst prior to the copolymerization. Successively, the slurry copolymerization of ethylene and an alpha -olefin is effected in a low-boiling diluent to obtain a low density polyethylene of 0.925-0.950 in density, covering various grades in a wide range.
Inventors
- 👤 Akira Ito
- 👤 Kenji Iwata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:50
CPC Classifications
C; C08; C08F; C08F297/00; C08F297/06; C08F297/08; C08F10/00; C08F10/02; C08F210/00; C08F210/02; C08F210/16; Y; Y10; Y10S; Y10S526/00; Y10S526/904
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
168 words
A method for the production of a low density copolymers of ethylene and α-olefins having a density of 0.925 to 0.950 g/ml and a bulk density of more than 0.35 g/ml by copolymerizing ethylene and an α-olefin, which comprises: (1) using a catalyst consisting of (A) titanium and/or vanadium compounds selected from the transition metal component of a Ziegler catalyst supported with a magnesium compound and (B) an organoaluminum compound, (2) subjecting ethylene to a pre-polymerization in a liquid diluent in the presence of said catalyst prior to in the copolymerization, the amount of ethylene to be prepolymerized being more than 50 g per 1.0 g of said catalyst component (A) and not more than 20% by weight of the entire amount of the ethylene and α-olefin monomers to be polymerized, and (3) successively, conducting the copolymerization of ethylene and an α-olefin at temperatures of not higher than 100° C. in the presence of a low-boiling hydrocarbon diluent having a boiling point of not higher than 40° C.
Claim 2
Independent Claim
168 words
A method for the production of a low density copolymers of ethylene and α-olefins having a density of 0.925 to 0.950 g/ml and a bulk density of more than 0.35 g/ml by copolymerizing ethylene and an α-olefin, which comprises: (1) using a catalyst consisting of (A) titanium and/or vanadium compounds selected from the transition metal component of a Ziegler catalyst supported with a magnesium compound and (B) an organoaluminum compound, (2) subjecting ethylene to a pre-polymerization in a liquid diluent in the presence of said catalyst prior to in the copolymerization, the amount of ethylene to be prepolymerized being more than 50 g per 1.0 g of said catalyst component (A) and not more than 20% by weight of the entire amount of the ethylene and α-olefin monomers to be polymerized, and (3) successively, conducting the copolymerization of ethylene and an α-olefin at temperatures of not higher than 100° C. in the presence of a low-boiling hydrocarbon diluent having a boiling point of not higher than 40° C.
Claim 3
Dependent Claim
27 words
The method according to claim 1 wherein the catalyst component (A) is one prepared by co-pulverizing the titanium and/or vanadium compounds, the magnesium compound and an additive.
Claim 4
Dependent Claim
30 words
The method according to claim 1 wherein the amount of ethylene to be pre-polymerized is in the range of 50 to 3000 g per 1 g of the component (A).
Claim 5
Dependent Claim
22 words
The method according to claim 1 wherein the copolymerization diluent is propane, n-butane, iso-butane, n-pentane, iso-pentane, cyclopropane or cyclobutane, or mixtures thereof.
Claim 6
Dependent Claim
26 words
The method according to claim 1 wherein the amount of α-olefin to be copolymerized is between about 0.5 and 12 weight % of the resulting copolymer.
Claim 7
Dependent Claim
20 words
The method according to claim 2, wherein said additive is selected from a siloxane polymer or an aluminum halide-ether complex.
Claim 8
Dependent Claim
26 words
The method according to claim 1, wherein said copolymer has a melt index of less than 0.1 measured in accordance with ASTM D-1238-65T (Test Condition E).
Claim 9
Dependent Claim
11 words
The method according to claim 1, wherein said diluent is propane.
Claim 10
Dependent Claim
11 words
The method according to claim 1, wherein said diluent is iso-butane.
Claim 11
Dependent Claim
11 words
The method according to claim 1, wherein said diluent is n-butane.
Claim 12
Dependent Claim
11 words
The method according to claim 1, wherein said α-olefin is butene-1.
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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) | 1983-02-25 | 1983-08-27 | 1984-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-25 | 1987-08-27 | 1988-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-25 | 1991-08-27 | 1992-02-26 | $7700.00 | Window Closed / Lapsed |