viton

FKM is a family of fluorocarbon-based fluoroelastomer materials defined by ASTM International standard D1418 and ISO standard 1629. It is commonly called fluorine rubber or fluoro-rubber. FKM is an abbreviation of Fluorkautschukmaterial (i.e. fluorine rubber material). All FKMs contain vinylidene fluoride as the common monomer, to which different other monomers are added for specific types and functionalities, fitting the desired application.
Originally developed by DuPont (under the brand name Viton, now owned by Chemours), FKMs are today also produced by many other companies, including Daikin (Dai-El), 3M (Dyneon), Solvay S.A. (Tecnoflon), HaloPolymer (Elaftor), Gujarat Fluorochemicals (Fluonox), and several Chinese manufacturers. Fluoroelastomers are more expensive than neoprene or nitrile rubber elastomers, and in comparison they provide additional resistance to heat and chemicals. There are three ways that the FKMs can be separated into classes: by their chemical composition, their fluorine content, or their cross-linking mechanism.

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