Patent US4113772A successfully refreshed from Google Patents.
US4113772A
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Method for producing perfluoroether oligomers having terminal carboxylic acid groups
Assignee: Individual
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Filing: 1975-07-21
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Granted: 1978-09-12
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Expires: 1995-07-21
Abstract
Abstract A method is disclosed for producing perfluoroether oligomers having terminal carboxylic acid groups. In this method, a polyether, such as polyethylene oxide, having a molecular weight higher than the product to be produced is fluorinated in a direct fluorination apparatus. The polyether is fragmented during fluorination and significant yields of the desired oligomer are obtained.
Inventors
- 👤 Richard J. Lagow
- 👤 Shoji Inoue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:12
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/32; C08G65/321; C08G65/323; C08G65/3233; C08G65/3236
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
70 words
A process for forming perfluoroether oligomers having terminal carboxylic acid groups comprising: a. placing a polyether having a molecular weight higher than the desired oligomer product in an enclosed reactor which is maintained at a temperature below the decomposition point of said polyether; and, b. directly fluorinating said polyether by introducing a source of elemental fluorine into said reactor until said perfluorinated polyether having terminal carboxylic acid groups is formed.
Claim 2
Dependent Claim
70 words
A process for forming perfluoroether oligomers having terminal carboxylic acid groups comprising: a. placing a polyether having a molecular weight higher than the desired oligomer product in an enclosed reactor which is maintained at a temperature below the decomposition point of said polyether; and, b. directly fluorinating said polyether by introducing a source of elemental fluorine into said reactor until said perfluorinated polyether having terminal carboxylic acid groups is formed.
Claim 3
Dependent Claim
11 words
A process of claim 1 wherein said polyether comprises polyethylene oxide.
Claim 4
Dependent Claim
14 words
A process of claim 2 wherein said source of elemental fluorine is fluorine gas.
Claim 5
Dependent Claim
16 words
A process of claim 3 wherein said elemental fluorine gas is diluted during said direct fluorination.
Claim 6
Dependent Claim
15 words
A process of claim 4 wherein said fluorine gas is diluted with an inert gas.
Claim 7
Dependent Claim
20 words
A process of claim 3 wherein oxygen is simultaneously introduced with elemental fluorine during said direct fluorination of said polyether.
Claim 8
Dependent Claim
24 words
A perfluorinated polyethylene oxide having a degree of polymerization above 5 and having terminal groups selected from acid fluoride groups and carboxylic acid groups.
Claim 9
Dependent Claim
24 words
A perfluorinated polyethylene oxide having a degree of polymerization above 5 and having terminal groups selected from acid fluoride groups and carboxylic acid groups.
Claim 10
Dependent Claim
18 words
A perfluorinated polyethylene oxide of claim 7 having a degree of polymerization between about 20 and about 25.
References Cited (Backward Citations)
US3250806A
Cited
US3250807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-11 | 1982-03-13 | 1982-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-11 | 1986-03-13 | 1986-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-11 | 1990-03-13 | 1990-09-12 | $7700.00 | Window Closed / Lapsed |