Patent EP0220910B1 successfully refreshed from Google Patents.
EP0220910B1
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EP
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Stable tetrafluoroethylene copolymers
Assignee: EIDP Inc
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Filing: 1986-10-20
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Granted: 1992-09-09
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Expires: 2006-10-20
Abstract
Abstract A tetrafluoroethylene/perfluoro(alkyl vinyl)ether copolymer substantially free of unstable end groups and extractable fluoride that cause corrosion of metal surfaces.
Inventors
- 👤 John Francis Imbalzano
- 👤 Dewey Lynn Kerbow
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 15:25
CPC Classifications
C; C08; C08F; C08F214/00; C08F214/18; C08F214/26; C08F214/262; B; B29; B29B; B29B9/00; B29B9/16; C08F8/00; C08F8/18; C08F8/20; C08F8/22; B29K; B29K2027/00; B29K2027/12
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
84 words
A melt-fabricable, nonelastomeric, tetrafluoroethylene copolymer substantially free of end groups that can react or decompose to emit HF, comprising recurring units of tetrafluoroethylene and at least one perfluoro(alkyl vinyl)ether where the alkyl group contains 1-8 carbon atoms and wherein the vinyl ether comprises between 1 and 10 weight percent of the copolymer; said copolymer characterized by having a) less than 6 endgroups of -CF₂CH₂OH, -CONH₂ and -COF per 10⁶ carbon atoms and b) an extractable fluoride level of 3 ppm or less by weight.
Claim 2
Dependent Claim
15 words
A copolymer according to Claim 1 wherein the perfluoro(alkyl vinyl)ether is a normal perfluoro(alkyl vinyl)ether.
Claim 3
Dependent Claim
12 words
A copolymer according to Claim 2 wherein the ether is perfluoro(propyl vinyl)ether.
Claim 4
Dependent Claim
22 words
A copolymer according to any one of Claims 1 to 3 wherein the ether content is between 2 and 4 weight percent.
Claim 5
Dependent Claim
85 words
A process for producing a copolymer as claimed in any one of claims 1 to 4 which comprises treating a said copolymer containing more than 6 per 10⁶ carbon atoms of end groups of -CF₂CH₂OH, -CONH₂ and -COF with a fluorine-containing gas at a temperature, time and pressure sufficient to reduce the end groups -CF₂CH₂OH, -CONH₂ and -COF to less than 6 per 10⁶ carbon atoms, and sparging the fluorinated copolymer with an inert gas until the sparge gas tests negative in the starch/iodide test.
References Cited (Backward Citations)
No citation records indexed.
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