Claims
- 1. A method for forming fluorocarbon ethers having perfluoralkyl groups, comprising:
- a. fluorinating a high molecular weight polyether under conditions which produce a fluorinated polyether;
- b. subjecting said fluorinated polyether to a temperature which is higher than the temperature used in the conditions in step a, and between approximately 55.degree. C. and 210.degree. C. to cause a controlled fragmentation of said polyether into lower molecular weight fluorocarbon ether compounds; and
- c. separating said fluorocarbon ether compounds from the reaction mixture.
- 2. A method of claim 1, where said fluorination is carried out with elemental fluorine gas.
- 3. A method of claim 1, where said high molecular weight polyether is perfluorinated to a perfluoropolyether.
- 4. A method of claim 1, where said high molecular weight polyether compound comprises a polyalkylene oxide ether wherein said alkylene group contains at least two carbon atoms.
- 5. A method of claim 4 wherein said poly(alkylene oxide)ether comprises polypropylene oxide.
- 6. A method of claim 1, where the high molecular weight polyether is polyethylene oxide and the lower molecular weight fluorocarbon ether compounds have the formula R.sub.f --O--(CF.sub.2 --CF.sub.2 --O).sub.n --R.sub.f, where n is 1-6 and R.sub.f is CF.sub.3 or C.sub.2 F.sub.5.
RELATED APPLICATIONS
This is a continuation of application Ser. No. 139,181 filed Apr. 11, 1980 which itself was a continuation-in-part of U.S. Ser. No. 901,905 filed May 1, 1978, both now abandoned.
GOVERNMENT SUPPORT
The invention described herein was made in the course of work partially supported by grants from the United States Air Force.
US Referenced Citations (5)
Number |
Name |
Date |
Kind |
3758450 |
Margrave et al. |
Sep 1973 |
|
3897502 |
Russell et al. |
Jul 1975 |
|
3985810 |
von Halasz et al. |
Oct 1976 |
|
4113772 |
Lagow et al. |
Sep 1978 |
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4281119 |
Lagow et al. |
Jul 1981 |
|
Continuations (1)
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Number |
Date |
Country |
Parent |
139181 |
Apr 1980 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
901905 |
May 1978 |
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