FFKM (or FFPM), also known as perfluorelastomer, is a family of elastomer materials with a fully fluorinated polymer backbone resulting in fluorine content of over 71%. This makes them elastomers with the best chemical resistance available. Chemical resistance is second to none, with good performance in a broad variety of harsh environments:  hot amines, steam, solvents, hydrocarbons etc. 

Depending on the type, FFKM also has to highest temperature resistance available for rubber materials. And especially the combination of high temperature and chemical resistance, FFKMs are solely on the top of the elastomer world. 

Traditionally, FFKM polymers have offered limited resistance to low temperatures, however, newer polymer chemistry now offers FFKM grades capable of sealing at temperatures down to -40°C.  

FFKMs exist in different types, mainly difference is based on the curing agents 

FFKM molecule

Common FFKM Types

Common FFKM Types

Curing Agent

High temperature resistance

Specific information

Common FFKM Types



Broad chemical resistance

Common FFKM Types



High temperature, excellent mechanical properties. Reduced chemical and steam resistance

Common FFKM Types

Modified Triazinic


Broad chemical resistance, excellent mechanical properties.

Common FFKM Types

Modified Peroxide


High temperature resistance, excellent mechanical properties, reduced amine and base resistance

A famous FFKM brand name is Kalrez from DuPont, for which ERIKS has a partnership with DuPont in many countries.   Additional, ERIKS has also an own-range of FFKM materials branded under XTR-Fluor, which is marketed in the UK. 

FFKMs are the most expensive rubber materials, and therefore a purely item-to-item price comparison with other rubber materials is not useful.  In some cases FFKMs are the only realistic option, but in other cases the use of FFKM might provide u huge benefit in Total Cost of Ownership (less machine or factory down-time, less repairs and inspections for greater productivity and yield, better equipment/machine performance, etc). 

FFKMs are used in different industries such as (petro)chem, food, pharma, oil&gas and semicon.  For clean high tech applications in semicon, electronics or optics, ERIKS has a special SCVBR® program, which can be found via this link. 

Strengths & Limitations

Temperature Resistance

  • low temperatures to -5/-15 degree C for most grades, and -40 for special ones
  • high temperatures up to 327 degree C, depending on the grade


Chemical & Ageing resistance


  • Almost everything, specific strengths depending on the type


  • Almost none  

Material Comparison

  • FFKM better high temperature resistance 
  • FFKM better overall chemical resistance 
  • FFKM higher price 

  • FFKM better high temperature resistance 
  • FFKM better overall chemical resistance 
  • FFKM higher price 

  • FFKM better high temperature resistance 
  • FFKM better chemical resistance 
  • FFKM mush higher price 
  • FFKM less good for low temperatures 

FFKM Compound overview

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