US4258168A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymerization process
Assignee: BP Corp North America Inc
•
Filing: 1976-06-16
•
Granted: 1981-03-24
•
Expires: 1996-06-16
Abstract
Abstract In an alpha-olefin polymerization process using a transition metal halide-aluminum alkyl catalyst system, addition of minor, effective amounts of alkyl orthoformates, thiophosphates and borates decreases the amount of low molecular weight or amorphous polymer produced.
Inventors
- 👤 Nicholas M. Karayannis
- 👤 Sam S. Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:42
CPC Classifications
C; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
78 words
In a process to polymerize alpha-olefins to normally-solid, substantially crystalline polymer utilizing a catalyst comprising a titanium halide and an aluminum alkyl, the improvement comprising adding to such catalyst effective amounts of an additive selected from the group consisting of aliphatic and aromatic esters of orthoformic and thiophosphoric acids wherein the aliphatic and aromatic groups are hydrocarbons or substituted hydrocarbons containing from 1 to about 12 carbon atoms, whereby the amount of n-hexane soluble polymeric product is decreased.
Claim 2
Dependent Claim
78 words
In a process to polymerize alpha-olefins to normally-solid, substantially crystalline polymer utilizing a catalyst comprising a titanium halide and an aluminum alkyl, the improvement comprising adding to such catalyst effective amounts of an additive selected from the group consisting of aliphatic and aromatic esters of orthoformic and thiophosphoric acids wherein the aliphatic and aromatic groups are hydrocarbons or substituted hydrocarbons containing from 1 to about 12 carbon atoms, whereby the amount of n-hexane soluble polymeric product is decreased.
Claim 3
Dependent Claim
17 words
The improvement of claim 1 wherein the alpha-olefin is propylene or a mixture of propylene and ethylene.
Claim 4
Dependent Claim
13 words
The improvement of claim 2 wherein the titanium halide is a titanium trichloride.
Claim 5
Dependent Claim
17 words
The improvement of claim 3 wherein the aluminum alkyl is diethylaluminum chloride, triethylaluminum or a mixture thereof.
Claim 6
Dependent Claim
15 words
The improvement of claim 4 wherein the additive is an alkyl ester of orthoformic acid.
Claim 7
Dependent Claim
15 words
The improvement of claim 4 wherein the additive is an alkyl ester of thiophosphoric acid.
Claim 8
Dependent Claim
13 words
The improvement of claim 5 wherein the additive is trimethylorthoformate, triethylorthoformate or tri-n-butylorthoformate.
Claim 9
Dependent Claim
14 words
The improvement of claim 6 wherein the additive is triethylthiophosphate, tri-n-butylthiophosphate, tri-isooctylthiophosphate or tri-p-tolylthiophosphate.
References Cited (Backward Citations)
US2956991A
Cited
US3502634A
Cited
US3149097A
Cited
US3149098A
Cited
US3269996A
Cited
US3278643A
Cited
US3940345A
Cited
US3984350A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-23 | 1984-09-22 | 1985-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-23 | 1988-09-22 | 1989-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-23 | 1992-09-22 | 1993-03-24 | $7700.00 | Window Closed / Lapsed |