Viton is a brand of synthetic rubber and fluoropolymer elastomer commonly used in O-rings and other moulded or extruded goods. The name is a registered trademark of DuPont Performance Elastomers L.L.C..
Viton fluoroelastomers are categorized under the ASTM D1418 & ISO 1629 designation of FKM. This class of elastomers is a family comprising copolymers of hexafluoropropylene (HFP) and vinylidene fluoride (VDF or VF2), terpolymers of tetrafluoroethylene (TFE), vinylidene fluoride (VDF) and hexafluoropropylene (HFP) as well as perfluoromethylvinylether (PMVE) containing specialties. The fluorine content of the most common Viton grades varies between 66 and 70%.
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