Claims
- 1. Modified polytetrafluoroethylene fine powder which comprises colloidal particles of a copolymer comprising repeating units of tetrafluoroethylene and 0.02 to 0.3% by weight of repeating units of a fluoroalkyl vinyl ether of the formula:
- X(CF.sub.2).sub.n OCF.dbd.CF.sub.2 (I)
- wherein X is a hydrogen, fluorine or chlorine atom and n is an integer of 1 to 6, wherein said colloidal particles have a number average particle size of 0.05 to 0.6 .mu.m, wherein said copolymer has a specific melt viscosity of from 6.times.10.sup.10 to 30.times.10.sup.10 poise at 380.degree. C. and a standard specific gravity of from 2.135 to 2.175 and wherein a paste extruded article of said copolymer has a green elongation of at least 400%.
- 2. The modified polytetrafluoroethylene fine powder according to claim 1, wherein the content of the fluoroalkyl vinyl ether is from 0.03 to 0.2% by weight.
- 3. The modified polytetrafluoroethylene fine powder according to claim 1, wherein the specific melt viscosity is from 8.0.times.10.sup.10 to 25.times.10.sup.10 poise at 380.degree. C.
- 4. The modified polytetrafluoroethylene fine powder according to claim 1, wherein the standard specific gravity is from 2.140 to 2.170.
- 5. The modified polytetrafluoroethylene fine powder according to claim 4, wherein the standard specific gravity is from 2.140 to 2.160.
- 6. The modified polytetrafluoroethylene fine powder according to claim 1, wherein the fluoroalkyl vinyl ether is C.sub.3 F.sub.7 OCF.dbd.CF.sub.2 or C.sub.4 F.sub.9 OCF.dbd.CF.sub.2.
- 7. The modified polytetrafluoroethylene fine powder according to claim 1, wherein the fluoroalkyl vinyl ether is ClC.sub.3 F.sub.6 OCF.dbd.CF.sub.2.
Priority Claims (1)
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62-156875 |
Jun 1987 |
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Parent Case Info
This application is a divisional of copending application Ser. No. 07/715,029, filed on Jun. 13, 1991, now U.S. Pat. No. 5,136,958 which is a continuation of Ser. No. 07/566,865 filed Aug. 13, 1990, now abandoned, which is a continuation of Ser. No. 07/445,937 filed Dec. 7, 1989, now U.S. Pat. No. 5,005,335, which is a continuation of Ser. No. 07/210,348 filed Jun. 23, 1988, now abandoned, the entire contents of which are hereby incorporated by reference.
US Referenced Citations (7)
Foreign Referenced Citations (2)
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0224037 |
Jun 1987 |
EPX |
2750566 |
May 1978 |
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Divisions (1)
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715029 |
Jun 1991 |
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Continuations (3)
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566865 |
Aug 1990 |
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445937 |
Dec 1989 |
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210348 |
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