Patent US3704285A successfully refreshed from Google Patents.
US3704285A
Expired / Lapsed
US
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Dispersion polymerization of tetrafluoroethylene
Assignee: EIDP Inc
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Filing: 1971-07-19
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Granted: 1972-11-28
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Expires: 1991-07-19
Abstract
Abstract A POLYMERIZATION PROCESS FOR PREPARING AN AQUEOUS DISPERSION OF POLYTETRAFLUOROETHYLENE RESENS INVOLVING USING BOTH A HYDROCARBON-BASED SURFACTANT AND A FLUOROCARBON-BASED SURFACENT AS NUCLEATORS FOR POLYMERIZATION FOLLOWED BY SUBSEQUENT INJECTION OF CHLORENDIC ACID AS STABILIZER AS THE POLYMERIZATION PROCEEDS TO NORMAL FINAL SOLIDS CONTENT. THE RESULTANT DISPERSION UPON COAGULATION AND DRYING YIELDS PRODUCTS CAPABLE OF BEING PASTE-EXTRUDED INTO TAPES, ETC., OF A HIGHER TENSILE STRENGTH FOR A GIVEN REDUCTION RATIO AND EXTRUSION PRESSURE THAN PREVIOUSLY ATTAINABLE DIRECTLY.
Inventors
- 👤 Verleon Henry Porter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:59
CPC Classifications
C; C08; C08F; C08F14/00; C08F14/18; C08F14/26
Claims Analysis
Total Claims: 0
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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) | 1975-11-28 | 1976-05-29 | 1976-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-28 | 1980-05-29 | 1980-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-28 | 1984-05-29 | 1984-11-28 | $7700.00 | Window Closed / Lapsed |