Viton® is a synthetic rubber and fluoropolymer elastomer commonly used in o-rings and other moulded or extruded goods. It is a trademark of DuPont Dow Elastomers L.L.C. (http://www.dupont-dow.com).

Viton® fluoroelastomers are categorized under the ASTM D1418 & ISO 1629 designation of FKM. This class of elastomers is a polymer 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%.

The performance of fluoroelastomers, e.g. in aggressive chemicals, depends on the nature of the base polymer chosen for the rubber compounds and the compounding ingredients used for moulding the final products (e.g. O-rings). This performance can vary significantly when end-users purchase Viton® polymer containing rubber goods from different sources.