Patent US4624988A successfully refreshed from Google Patents.
US4624988A
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Curing of thermoplastic tetrafluoroethylene/perfluoroalkyl ethylene copolymers
Assignee: EIDP Inc
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Filing: 1985-10-21
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Granted: 1986-11-25
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Expires: 2005-10-21
Abstract
Abstract Crosslinking of copolymers of tetrafluoroethylene and perfluoroalkylethylene by heating in the presence of K 2 AF is described.
Inventors
- 👤 Scott J. Fritschel
- 👤 William D. Saunders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:59
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/13; C08K5/138
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
42 words
A process for crosslinking non-elastomeric, melt-fabricable fluorocarbon copolymers of tetrafluoroethylene and perfluoroalkyl ethylene which comprises treating the copolymer with the dipotassium salt of bis-phenol AF in an amount effective to cause crosslinking and heating the copolymer at 300°-340° C. for 4-30 minutes.
Claim 2
Dependent Claim
42 words
A process for crosslinking non-elastomeric, melt-fabricable fluorocarbon copolymers of tetrafluoroethylene and perfluoroalkyl ethylene which comprises treating the copolymer with the dipotassium salt of bis-phenol AF in an amount effective to cause crosslinking and heating the copolymer at 300°-340° C. for 4-30 minutes.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein the copolymer comprises tetrafluoroethylene and perfluorobutyl ethylene.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-24 | 1990-05-26 | 1990-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-24 | 1994-05-26 | 1994-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-24 | 1998-05-26 | 1998-11-25 | $7700.00 | Window Closed / Lapsed |