Claims
- 1. A composition, comprising, a solution in liquid or supercritical carbon dioxide of a fluoropolymer, wherein said fluoropolymer:
- has a ratio of backbone hydrogen:fluorine atoms of about 0.3 to about 1.0;
- has a melting point, if any, of about 100.degree. C. or less;
- contains only carbon, hydrogen, fluorine, and optionally ether oxygen; and
- has a weight average molecular weight of about 5,000 or more.
- 2. The composition as recited in claim 1 wherein said fluoropolymer has a weight average molecular weight of about 10,000 or more.
- 3. The composition as recited in claim 1 wherein said fluoropolymer contains repeat units derived from one or more of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride.
- 4. The composition as recited in claim 1 wherein said fluoropolymer has no melting point above 0.degree. C.
- 5. The composition as recited in claim 4 wherein said fluoropolymer is a copolymer of tetrafluoroethylene and vinylidene fluoride; hexafluoropropylene and vinylidene fluoride; tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride; tetrafluoroethylene, hexafluoropropylene and ethylene; tetrafluoro-ethylene, hexafluoropropylene and vinyl fluoride; or tetrafluoroethylene, hexafluoropropylene and propylene.
- 6. A process for making a solution of a fluoropolymer in carbon dioxide, comprising, contacting liquid or supercritical carbon dioxide with said fluoropolymer at a temperature of about 100.degree. C. or less and a pressure of about 41 MPa (6,000 psi) or less, wherein said fluoropolymer:
- has a ratio of backbone hydrogen:fluorine atoms of about 0.3 to about 1.0,
- has a melting point, if any, of about 100.degree. C. or less;
- contains only carbon, hydrogen, fluorine, and optionally ether oxygen; and
- has a weight average molecular weight of about 5,000 or more.
- 7. The process as recited in claim 6 wherein said fluoropolymer has a weight average molecular weight of about 10,000 or more.
- 8. The process as recited in claim 6 wherein said fluoropolymer contains repeat units derived from one or more of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride.
- 9. The process as recited in claim 6 wherein said fluoropolymer has no melting point above 0.degree. C.
- 10. The process as recited in claim 9 wherein said fluoropolymer is a copolymer of tetrafluoroethylene and vinylidene fluoride; hexafluoropropylene and vinylidene fluoride; tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride; tetrafluoroethylene, hexafluoropropylene and ethylene; tetrafluoro-ethylene, hexafluoropropylene and vinyl fluoride; or tetrafluoroethylene, hexafluoropropylene and propylene.
- 11. The process as recited in claim 6 wherein said temperature is about 50.degree. C. or less.
- 12. The process as recited in claim 6 wherein said pressure is about 31 MPa or less.
Parent Case Info
This application claims priority benefit of U.S. Provisional Application Ser. No. 60/062,276, filed Oct. 17, 1997.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
5496901 |
DeSimone |
Mar 1996 |
|
5530049 |
Dee et al. |
Jun 1996 |
|
5618894 |
DeSimone et al. |
Apr 1997 |
|