Fluorocopolymer and fluororesin composition lowly permeable to liquid chemical
US6774196B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 2002 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | May 28, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F214/262
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
To provide a novel PFA-based fluorine-containing copolymer having improved impermeability to liquid chemicals while retaining the excellent heat resistance, stress cracking resistance and processability inherent in PFA-based fluororesins, a material and a molded article useful in the field of semiconductor production apparatus and the like, using the copolymer. The present invention provides a fluorine-containing copolymer comprising 90 to 99.4% by mole of a repeating unit derived from tetrafluoroethylene, 0.5 to 5% by mole of a repeating unit derived from at least one lower perfluoro(alkyl vinyl ether) represented by the formula (1):CF2═CF—O—Rf1  (1)in which Rf1 is a perfluoroalkyl group having 2 to 4 carbon atoms, and 0.1 to 5% by mole of a repeating unit derived from at least one higher perfluoro(vinyl ether) represented by the formula (2):CF2═CF—O—Rf2  (2)in which Rf2 is a perfluoroalkyl group having 5 to 10 carbon atoms or a perfluoro(alkoxy alkyl) group having 4 to 17 carbon atoms, wherein the fluorine-containing copolymer has a melt flow rate of 0.1 g/10 minutes to 100 g/10 minutes and melting point of 290° to 325…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.