The name "perfluoroelastomer" is somewhat misleading. An actual perfluorinated material with a high molecular weight is polytetrafluoroethylene or PTFE which has the chemical formula "(CF2)n." The molecular carbon chain is shielded by the chemical inertness of the large bonded fluorine atoms. Perfluoroelastomer is produced by the copolymerization of tetrafluoroethylene (TFE) and a perfluorinated ether, e.g. perfluoromethylvinylether (PMVE). The differing resistance to volume swell of the different perfluoroelastomers is due to the perfluorinated ether element, where the side-chain can consist of up to four perfluorinated carbon atoms. The extraordinary chemical resistance is partly due to the fluorine atoms shielding the carbon chain, and partially due to the vulcanization system.
Heat resistance:
450°F to 600°F (232°C to 316°C) depending on compound.
Cold flexibility:
0°F to –15°F (–18°C to –26°C).
Chemical resistance:
Aliphatic and aromatic hydrocarbons
Chlorinated hydrocarbons
Polar solvents (acetone, methylethylketone, ethylacetate, diethylether and dioxane)
Inorganic and organic acids
Water and steam
High vacuum with minimal loss in weight.
Not compatible with:
Fluorinated refrigerants (R11, 12, 13, 113, 114, etc.).
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