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US3893971A
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Stabilized ethylene-tetrafluoroethylene copolymer composition
Assignee: AGC Inc
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Filing: 1973-12-26
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Granted: 1975-07-08
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Expires: 1993-12-26
Abstract
Abstract Ethylene-tetrafluoroethylene copolymer compositions are stabilized against thermal degradation so as to render them meltprocessable by imcorporating therein 0.001 to 5 weight percent of Alpha -alumina, based on the weight of copolymer in the compositions.
Inventors
- 👤 Hiroshi Ukihashi
- 👤 Masaaki Yamabe
- 👤 Hiromichi Nishimura
- 👤 Haruhisa Miyake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:34
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
42 words
AN ETHYLENE-TETRAFLUOROETHYLENE COPOLYMER COMPOSITION HAVING IMPROVED THERMAL STABILITY, WHICH COMPRISES: AN ADMIXTURE OF AN ETHYLENE-TETRAFLUOROETHYLENE COPOLYMER, WHEREIN THE MOLD RATIO OF TETRAFLUOROETHYLENE TO ETHYLENE IS 40-70/60-30 AND FROM 0.001 TO 5 WT. % OF A-ALUMINA, BASED ON THE WEIGHT OF THE COPOLYMER.
Claim 2
Dependent Claim
42 words
AN ETHYLENE-TETRAFLUOROETHYLENE COPOLYMER COMPOSITION HAVING IMPROVED THERMAL STABILITY, WHICH COMPRISES: AN ADMIXTURE OF AN ETHYLENE-TETRAFLUOROETHYLENE COPOLYMER, WHEREIN THE MOLD RATIO OF TETRAFLUOROETHYLENE TO ETHYLENE IS 40-70/60-30 AND FROM 0.001 TO 5 WT. % OF A-ALUMINA, BASED ON THE WEIGHT OF THE COPOLYMER.
Claim 3
Dependent Claim
20 words
The composition of claim 1, wherein the copolymer has a volumetric melt flow rate of about 10 - 300 mm3/sec.
Claim 4
Dependent Claim
26 words
The composition of claim 1, wherein the copolymer has a flow initiation temperature of 260* -300 *C and a thermal decomposition temperature of 320* - 360*C.
Claim 5
Dependent Claim
29 words
The composition of claim 1, wherein the Alpha -alumina has an average particle diameter of less than 100 Mu and a specific surface area from 0.5 - 5 2/g.
Claim 6
Dependent Claim
18 words
The composition of claim 1, wherein the Alpha -alumina is calcined at a temperature higher than about 900*C.
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) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |