Perfluoroether
Perfluoroethers are a class of organofluorine compound containing one or more ether functional group. In general these compounds are structural analogous to related hydrocarbon ethers, but they exhibit to the distinctive properties of fluorocarbons.
Acyclic perfluoroethers are known, e.g. O(C2F5)2, the analogue of diethylether. More interesting and more useful are the cyclic ethers, especially, the epoxides. Thus tetrafluoroethyene oxide and hexafluoropropylene oxide are two of the simplest cyclic perfluoroethers. It is a precursor to perfluoro(methyl vinyl ether) (CF2=CFOCF3) and perfluoro(propyl vinyl ether) are used as a comonomers with tetrafluoroethylene.
Perfluoroalkoxy alkanes (PFAs) are fluoropolymers with properties similar to polytetrafluoroethylene (PTFE) prepared polytetrafluoroethylene perfluoro methylvinylether, with a different ratio of PTFE and MVE monomers from PFA, is MFA. In these materials, the ether groups are pendant from the polymer backbone.
Krytox is a grease generated by the polymerization of hexafluoropropylene oxide. Their chemical formula is F−(CF(CF3)−CF2−O)n−CF2CF3. The ether groups are integral to the polymer chain.
Nafion is a perfluorinated polyether with pendant sulfonic acid groups (RSO3H).
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