- Fluoroelastomer
A Fluoroelastomer is a special purpose
synthetic rubber . It has wide chemical resistance and superior performance, especially in high temperature application in different media.Fluoroelastomers are categorized under the
ASTM D1418 &ISO 1629 designation of FKM. This class ofelastomer s is a family comprisingcopolymer s ofhexafluoropropylene (HFP) andvinylidene fluoride (VDF or VF2),terpolymer s oftetrafluoroethylene (TFE),vinylidene fluoride (VDF) andhexafluoropropylene (HFP) as well asperfluoromethylvinylether (PMVE) containing specialties. Thefluorine content of the most common grades varies between 66 and 70%.Main families of polymers
* Dipolymers of VF2/HFP, like
Viton A andTecnoflon [Tecnoflon is a registered trademark of Solvay Solexis S.p.A.] : General purpose sealing. Automotive, Aerospace fuels & lubricants
* Terpolymers of VF2/HFP/TFE, like Viton B and Tecnoflon: Chemical Process plant, Power Utility Seals & Gaskets
* Terpolymers of VF2/HFP/TFE, like Viton F and Tecnoflon: Oxygenated Automotive fuels. Concentrated aqueous inorganic acids, water, steam.
*Peroxide curable polymers are similar to terpolymers. They offer better chemical resistance than corresponding terpolymers with the same fluorine percentage.
*Low temperature polymers are typically peroxide curable with an additional monomer of PMVE.Performance
The performance of fluoroelastomers in aggressive chemicals depends on the nature of the base polymer and the compounding ingredients used for moulding the final products (e.g. O-rings, shaft seals). This performance can vary significantly when end-users purchase polymer containing rubber goods from different sources. Fluoroelastomers are generally compatible with hydrocarbons, but incompatible with
ketone s such asacetone and organic acids such asacetic acid .External links
* [http://www.zrunek.at/download/ZruElast%20FPM%20UK.pdf Designing with Fluoroelastomers]
* [http://www.solvaysolexis.com/static/wma/pdf/6/9/0/5/FKM_Guide_rev113004.pdf A Guide to Fluoroelastomers]References
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