Claims
- 1. An ionically vulcanizable fluoroelastomeric copolymer exhibiting improved compression set characteristics suitable for the production of O-rings, consisting essentially of the following non-brominated monomeric units:
- (a) 48-65% by weight of vinylidene fluoride (VDF);
- (b) 21-36% by weight of hexafluoropropene (HFP);
- (c) 3-9% by weight of perfluoroalkylvinylether (PAVE); and
- (d) 0-17% by weight of tetrafluoroethylene (TFE); wherein the sum of the HFP and PAVE contents is at least 27 weight %.
- 2. The fluoroelastomeric copolymer of claim 1, wherein the percentage by weight of component (c) is 4-8%.
- 3. The fluoroelastomeric copolymer of claim 1, wherein the percentages by weight of components (a), (c) and (d) are:
- (a) 60.5-64%,
- (c) 5-8%; and
- (d) 0-8%;
- and the sum of the HFP and PAVE contents is 30-33% by weight.
- 4. The ionically vulcanizable fluoroelastomeric copolymer of claim 1, wherein component (c) is selected from the group consisting of perfluoromethylvinylether, perfluorethylvinylether and perfluoropropylvinylether.
Priority Claims (1)
Number |
Date |
Country |
Kind |
MI 91 A 002040 |
Jul 1991 |
ITX |
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Parent Case Info
This is a continuation of U.S. application Ser. No. 07/744,778, filed Aug. 14, 1991, now abandoned which is incorporated by reference herein.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4123603 |
Stewart, Jr. |
Oct 1978 |
|
4745165 |
Arcella et al. |
May 1988 |
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Foreign Referenced Citations (1)
Number |
Date |
Country |
407937 |
Jan 1991 |
EPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
744778 |
Aug 1991 |
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