What are fluorosilicones - FVMQ?

Fluorosilicone rubber or fluorovinylmethylsiloxane – FVMQ is a variation of silicone rubber with a methyl, vinyl and fluorine group that maintains excellent high temperature stability and mechanical properties, while providing greater resistance to fuel, oil and other chemicals.

Fluorosilicones - Better chemical resistance than silicones

Fluorosilicone rubber – FVMQ has many of the attributes of silicone. For example, FVMQ rubbers have similar mechanical and physical properties and provide excellent chemical resistance to dilute acids and alkalis, as well as non-polar fluids such as petroleum oils, hydrocarbons, diesters and silicone oils. However, they have only average resistance to polar fluids like alcohols and low resistance to ketones, aldehydes, amines and brake fluids (non-petroleum based). They also have lower hot air resistance than silicone rubbers (VMQ).

Like all silicone elastomers, they have high heat and oxidation stability, exceptional low temperature flexibility and are resistant to heat, ozone and sunlight (UV). They also offer a similar wide operating temperature range, much wider than that of fluorocarbon rubbers.

Summary of the properties of fluorosilicones - FVMQ


  • Good resistance to mineral oils
  • Electrical insulator
  • Chemical Inertia
  • Good resistance to fuels
  • Good compression set at high temperatures
  • Good level of gas permeability
  • Excellent hot water and vapor resistance
  • Operating temperature: -50°C to +200°C


  • Resistance to ketones, aldehydes, amines and brake fluids
  • Hot air resistance
  • Abrasion and tear resistance

Fluorosilicone – FVMQ approvals

  • NFL 17-261
  • NFL 17-163

Applications of fluorosilicones - FVMQ

Fluorosilicones are used for sealing applications in the aerospace industry requiring resistance to hot fuels, oils and diester-based lubricants. They are often a good choice for static sealing systems for a wide temperature range. Their use is normally limited to static applications due to poor abrasion resistance, relatively low tear strength, and fair flexural cracking resistance.

Fluorosilicone - FVMQ brands

Fluorosilicone rubbers are also marketed under several brands, including the following:

  • FSE Momentive®,
  • FE Shin Etsu®
  • Silastic®