The name "perfluoroelastomer" is
somewhat misleading. An actual perfluorinated material with
a high molecular weight is polytetrafluoroethylene or PTFE.
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 ele¬ment, 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
• 232°C to 300°C (450°F to 590°F) depending
on com¬pound.
Cold flexibility
• -18°C to -26°C (0°F to -15°F).
Chemical resistance
• Aliphatic and aromatic hydrocarbons.
• Chlorinated hydrocarbons.
• Polarsolvents (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.)
|
