FFKM
Perfluorelastomers (FFKM) have a fully fluorinated polymer backbone resulting in fluorine content of over 71%.
As the material is free from carbon-hydrogen bonds in the polymer chain, the FFKM materials offer the ultimate thermochemical resistance. This is demonstrated by the good long term, high-temperature, compression set resistance. Chemical resistance is second to none, with good performance in a broad variety of harsh environments: hot amines, steam, solvents, hydrocarbons etc.
Traditionally, FFKM polymers have offered limited resistance to low temperatures, however, new polymer chemistry now offers FFKM grades capable of sealing at temperatures down to -40°C.
Although all FFKM polymer backbones are fully fluorinated the cross linking systems used to join the polymer chains together differ significantly, resulting in differing temperature and chemical resistance.
Types of Perfluoroelastomers
| Common FFKM Types | ||
|---|---|---|
| Peroxide | 240oC |
Broad chemical resistance |
| Triazinic | 327oC |
High temperature, excellent mechanical properties. Reduced chemical and steam resistance |
|
Modified Triazinic |
275oC | Broad chemical resistance, excellent mechanical properties. |
|
Modified Peroxide |
325oC | High temperature resistance, excellent mechanical properties, reduced amine and base resistance |