US4076760A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of fluorocarbon waxes
Assignee: Hoechst AG
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Filing: 1975-03-24
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Granted: 1978-02-28
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Expires: 1995-03-24
Abstract
Abstract The present invention relates to a process for the preparation of low molecular weight fluorocarbon waxes by thermic cracking of polytetrafluoroethylene or copolymers of tetrafluoroethylene and higher perfluoro-olefins at elevated temperatures and under increased pressure.
Inventors
- 👤 Robert Hartwimmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:28
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/50; C08F2810/00; C08F2810/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
Process for the preparation of solid fluorocarbon waxes which process consists essentially of thermic cracking of polytetrafluorethylene or copolymers of tetrafluorethylene and higher perfluoro-olefins at elevated temperatures and under increased pressures, wherein the pyrolysis is carried out at temperatures of from 350° to 700° C and under partial pressures of the degradation products of from 5 to 100 atmospheres gauge.
Claim 2
Dependent Claim
60 words
Process for the preparation of solid fluorocarbon waxes which process consists essentially of thermic cracking of polytetrafluorethylene or copolymers of tetrafluorethylene and higher perfluoro-olefins at elevated temperatures and under increased pressures, wherein the pyrolysis is carried out at temperatures of from 350° to 700° C and under partial pressures of the degradation products of from 5 to 100 atmospheres gauge.
Claim 3
Dependent Claim
20 words
Process as claimed in claim 1, wherein the pyrolysis is carried out at temperatures of from 450° to 600° C.
Claim 4
Dependent Claim
29 words
process as claimed in claim 1, wherein the pyrolysis is carried out under partial pressures of the decomposition products in the range of from 15 to 60 atmospheres gauge.
Claim 5
Dependent Claim
29 words
Process as claimed in claim 2 wherein the pyrolysis is carried out under partial pressures of the decomposition products in the range of from 15 to 60 atmospheres gauge.
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) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |