Aqueous emulsion polymerization of functionalized fluoromonomers
US7071271B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2003 |
| Grant date | Jul 4, 2006 |
| Priority date | — |
| Expiry date | Oct 30, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F214/184
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method is provided for aqueous emulsion co-polymerization of two or more fluoromonomers comprising the steps of: 1) forming an aqueous pre-emulsion by mixing a fluoromonomer according to formula I:F2C═CF—R1—SO2X (I)wherein R1 is a branched or unbranched perfluoroalkyl, perfluoroalkoxy or perfluoroether group comprising 1–15 carbon atoms and 0–4 oxygen atoms and wherein X is F, Cl or Br, together with 0.001–0.9 molar equivalents of a base, in the absence of added emulsifier; and 2) reacting the pre-emulsion with one or more perfluorinated comonomers in the absence of added emulsifier so as to form a fluoropolymer latex comprising a fluoropolymer wherein more than 1 mol % of monomer units are derived from the fluoromonomer according to formula I. In another aspect, the present invention provides a fluoropolymer derived from the fluoropolymer latex made according to the method of the present invention which is free of added emulsifier. In another aspect, the present invention provides a polymer electrolyte membrane comprising the fluoropolymer made according to the method of the present invention which is free of added emulsifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.