US3674761A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the preparation of ethylene-carboxylic acid copolymers
Assignee: Gulf Research and Development Co
•
Filing: 1970-09-09
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Granted: 1972-07-04
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Expires: 1990-09-09
Abstract
Abstract An ethylene-carboxylic acid copolymer is prepared by the thermal decomposition of an ethylene-isopropyl ester of acrylic or methacrylic acid in the presence of controlled concentrations of water vapor or ammonia.
Inventors
- 👤 Harry D Anspon
- 👤 Bert H Clampitt
- 👤 Ronald E Gilbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:36
CPC Classifications
C; C08; C08F; C08F8/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
16 words
The process of claim 1 wherein the heating step is conducted in a melt extrusion zone.
Claim 2
Dependent Claim
11 words
The process of claim 1 wherein said acid is acrylic acid.
Claim 3
Dependent Claim
152 words
In a process for the preparation of ethylene-carboxylic acid polymers which comprises heating an ethylene-isopropyl ester of acrylic or methacrylic acid copolymer to the ester decomposition temperature of at least 325* C., in the presence of a gas selected from the group consisting of steam and ammonia, maintaining said ethylene-isopropyl ester of acrylic or methacrylic acid at the thermal decomposition temperature until at least a portion of the isopropyl ester groups are decomposed, the ethylene concentration of the ethylene polymer to be heated being at least 2 mols per mol of contained isopropyl ester; the improvement which comprises adjusting the rate of flow of gas to the heating zone responsive to the melt index of the ethylene-acrylic or methacrylic acid copolymer withdrawn from the heating zone while maintaining a concentration of greater than one and not more than 500 mols of said gas per mol of isopropyl ester in said heating zone.
Claim 4
Dependent Claim
39 words
The process of claim 4 wherein said gas is steam and wherein said rate of flow of gas to said heating zone is maintained in the range between 1 and 500 mols of steam per mol of isopropyl ester.
Claim 5
Dependent Claim
16 words
The process of claim 4 wherein the heating step is conducted in a melt extrusion zone.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |