Patent US3718558A successfully refreshed from Google Patents.
US3718558A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing a cross-linked copolymer of tetrafluoroethylene and propylene using high energy ionizing radiation
Assignee: AGC Inc
•
Filing: 1970-12-11
•
Granted: 1973-02-27
•
Expires: 1990-12-11
Abstract
Abstract A cross-linked copolymer of tetrafluoroethylene and propylene is produced by irradiating a copolymer of tetrafluoroethylene and propylene in the absence of monomers of tetrafluoroethylene, propylene, or other copolymerizable monomer, with high energy ionizing radiation.
Inventors
- 👤 Y Tabata
- 👤 G Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:23
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/28; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
24 words
The process of claim 1 in which said copolymer is irradiated in the absence of any monomer of tetrafluoroethylene, propylene, or other copolymerizable monomer.
Claim 2
Dependent Claim
20 words
The process of claim 1, in which a shaped copolymer of tetrafluoroethylene and propylene is exposed to the irradiation treatment.
Claim 3
Dependent Claim
16 words
The process of claim 1, wherein the total dose is from 105 -5 X 107 Rads.
Claim 4
Dependent Claim
12 words
The process of claim 1, wherein said copolymer is irradiated in vacuum.
Claim 5
Dependent Claim
107 words
A cross-linked copolymer of tetrafluoroethylene and propylene which is characterized by an ultimate elongation of greater than 200%, an ultimate tensile strength of greater than 80 kg/cm2, and a decomposition temperature of more than 300* C. which is produced by irradiating a copolymer of tetrafluoroethylene and propylene having an average molecular weight of more than 20,000 and an intrinsic viscosity in tetrahydrofuran at 30* C. of more than 0.25, wherein the mole ratio of tetrafluoroethylene to propylene is from 90/10 to 20/80, with high energy ionizing radiation at a total dose of 105 - 5 X 107 Rads, and a dose rate of 102 to 109 roentgens/hour.
References Cited (Backward Citations)
US3467635A
Cited
US3556965A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |