US3892641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing a copolymer of tetrafluoroethylene and propylene
Assignee: Japan Atomic Energy Agency
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Filing: 1973-04-10
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Granted: 1975-07-01
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Expires: 1993-04-10
Abstract
Abstract High molecular weight copolymers of tetrafluoroethylene and propylene are prepared by a radiation-induced emulsion copolymerization process in the absence of a hydrocarbon liquid.
Inventors
- 👤 Yoneho Tabata
- 👤 Hiroshi Ukihashi
- 👤 Masaaki Yamabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:11
CPC Classifications
C; C08; C08F; C08F214/00; C08F214/18; C08F214/26; C08F214/265; C08F210/00; C08F210/04; C08F210/06; Y; Y10; Y10S; Y10S522/00; Y10S522/911
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
81 words
A PROCESS FOR PRODUCING COPOLYMER OF TETRAFLUOROETHYLENE AND PROPYLENE WHICH COMPRISES COPOLYMERIZING TETRAFLUOROETHYLENE AND PROPYLENE WITH HIGH ENERGY IONIZING RADIATION AT A DOSE RATE OF 10**2 - 10**7 ROENTGENS/HOUR IN AN AQUEOUS EMULSION, WITHOUT A HYDROCARBON LIQUID, CONSISTING ESSENTIALLY OF WATER, TETRAFLUOROETHYLENE AND PROPYLENE AND A DISPERSING AGENT WHICH IS SUITABLE FOR EMULSIFYING TETRAFLUOROETHYLENE AND PROPYLENE AND HAS NO RETARDING ACTION FOR THE COPOLYMERIZATION REACTION, WHEREIN THE REACTION TEMPERATURE IS 5* TO 80*C. AND REACTION PRESSURE IS 1 TO 50 KG/CM2.
Claim 2
Dependent Claim
81 words
A PROCESS FOR PRODUCING COPOLYMER OF TETRAFLUOROETHYLENE AND PROPYLENE WHICH COMPRISES COPOLYMERIZING TETRAFLUOROETHYLENE AND PROPYLENE WITH HIGH ENERGY IONIZING RADIATION AT A DOSE RATE OF 10**2 - 10**7 ROENTGENS/HOUR IN AN AQUEOUS EMULSION, WITHOUT A HYDROCARBON LIQUID, CONSISTING ESSENTIALLY OF WATER, TETRAFLUOROETHYLENE AND PROPYLENE AND A DISPERSING AGENT WHICH IS SUITABLE FOR EMULSIFYING TETRAFLUOROETHYLENE AND PROPYLENE AND HAS NO RETARDING ACTION FOR THE COPOLYMERIZATION REACTION, WHEREIN THE REACTION TEMPERATURE IS 5* TO 80*C. AND REACTION PRESSURE IS 1 TO 50 KG/CM2.
Claim 3
Dependent Claim
17 words
The process of claim 1, wherein the molar ratio of tetrafluoroethylene to propylene is 95/5 to 50/50.
Claim 4
Dependent Claim
16 words
The process of claim 1, wherein the dispersing agent is a perfluoro or perflurochloro dispersing agent.
Claim 5
Dependent Claim
23 words
The process of claim 1, wherein the amount of the dispersing agent is 0.001 - 5 percent by weight of the aqueous medium.
Claim 6
Dependent Claim
26 words
The process of claim 1, wherein the copolymer has an intrinsic viscosity, measured in a tetrahydrofuran solution (100 cc/g) at 30*C, of from 0.41 to 0.82.
Claim 7
Dependent Claim
17 words
The process of claim 1, wherein the total dose of radiation is from 102 - 108 roentgens.
Claim 8
Dependent Claim
37 words
The process of claim 3, wherein the dispersing agent is selected from the groups consisting of water soluble salts of perfluoro aliphatic carboxylic acid, water soluble salts of phosphoric esters of perfluoro aliphatic alcohol, perfluorosulfates and perfluorochlorosulfates.
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) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |