Patent EP0275620A2 successfully refreshed from Google Patents.
EP0224037A2
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EP
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Melt processible tetrafluoroethylene copolymer granules
Assignee: EIDP Inc
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Filing: 1986-10-23
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Granted: —
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Expires: 2006-10-23
Abstract
Abstract This invention relates to a process for preparing melt-processible tetrafluoroethylene perfluoro(alkyl vinyl ether) (TFE/PAVE) copolymer granules having good particle flow characteristics and thermal stability, and to the product of the process.
Inventors
- 👤 Marlin Dwight Buckmaster
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 20:36
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08F; C08F6/00; C08F6/24; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A process for treating a melt-processible, substantially nonelastomeric tetrafluoroethylene/perfluoro(alkyl vinyl ether) . copolymer where the alkyl group is of l-8 carbon atoms and the ether is present in amounts of between l and l0 weight %, that was prepared in a halocarbon solvent, which comprises A. contacting the copolymer in its halocarbon polymerization liquor with water in a ratio of l/l0 to 2/l by volume, while agitating the mixture and heating at 20 to l00°C, B. venting the halocarbon solvent while maintaining heat and agitation, C. removing water from the separated fluoropolymer granules and drying them, D. hardening the granules by heating the dried copolymer at a temperature between 25°C below its differential scanning calorimeter melt onset temperature and its initial melt endotherm peak temperature.
Claim 2
Dependent Claim
125 words
A process for treating a melt-processible, substantially nonelastomeric tetrafluoroethylene/perfluoro(alkyl vinyl ether) . copolymer where the alkyl group is of l-8 carbon atoms and the ether is present in amounts of between l and l0 weight %, that was prepared in a halocarbon solvent, which comprises A. contacting the copolymer in its halocarbon polymerization liquor with water in a ratio of l/l0 to 2/l by volume, while agitating the mixture and heating at 20 to l00°C, B. venting the halocarbon solvent while maintaining heat and agitation, C. removing water from the separated fluoropolymer granules and drying them, D. hardening the granules by heating the dried copolymer at a temperature between 25°C below its differential scanning calorimeter melt onset temperature and its initial melt endotherm peak temperature.
Claim 3
Dependent Claim
13 words
The process of Claim l wherein the copolymerizable comonomer is perfluoro(propyl vinyl ether).
Claim 4
Dependent Claim
70 words
A tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer wherein the alkyl group contains l-8 carbon atoms and the ether is present in an amount between l and l0 weight %, said copolymer having (a) a melt viscosity between l × l0³ and l × l0⁶ poise at 372°C. (b) a substantially spherical particle shape, (c) an Attrition Factor of less than 30, and (d) an average particle size between l00 and 3000 micrometers.
Claim 5
Dependent Claim
70 words
A tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer wherein the alkyl group contains l-8 carbon atoms and the ether is present in an amount between l and l0 weight %, said copolymer having (a) a melt viscosity between l × l0³ and l × l0⁶ poise at 372°C. (b) a substantially spherical particle shape, (c) an Attrition Factor of less than 30, and (d) an average particle size between l00 and 3000 micrometers.
Claim 6
Dependent Claim
13 words
The product of Claim 3 wherein the copolymerizable comonomer is perfluoro(propyl vinyl ether).
References Cited (Backward Citations)
No citation records indexed.
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