Viton has excellent resistance to high temperatures, ozone, oxygen, mineral oil, synthetic hydraulic fluids, fuels, aromatics and many organic solvents and chemicals. Low temperature resistance is normally not favorable and for static applications is limited to approximately -26°C (-15°F) although certain compounds are suitable down to -46°C (-50°F). Under dynamic conditions, the lowest service temperature is between -15°C and -18°C (5°F and 0°F). Gas permeability is very low and similar to that of butyl rubber. Special FKM compounds exhibit an improved resistance to acids and fuels
Buna O-rings, NBR or Nitrile O-rings offer excellent sealing properties and mechanical properties with low cost. Buna and Nitrile O-rings have a basic resistance to common lubricants and are recommended for crude oil, gasoline, propane, petroleum oils and water. Nitrile and Buna O-rings are used in engines, gearboxes, aircraft pumps, and common water applications.
Silicone o-rings offer wide temperature ranges and low temperature flexibility. Silicone is renowned for its retention of flexibility and low compression set characteristics
EPDM o rings have excellent resistance to ozone, weathering and sunlight. They have good heat resistance, low compression set and good flexibility at low temperatures
Neoprene O rings provides good resistence to UV, oxygen and weather applications. Neoprene o rings are commonly used in the refrigeration industry due to excellent resistance to ammonia and freon. Neoprene o-rings offer a range of operating temperatures
Fluorosilicone O rings are recommended for general purpose service in aerospace and fuel applications, and provide good high, low temperature performance in sealing fuels and mineral oils. Fluorosilicone rubber is a widely used elastomer that can be compounded to meet a wide range of applications. The mechanical and physical properties are very similar to silicone rubber. However, fluorosilicone offers improved fuels and mineral oil resistance but poor hot air resistance when compared with silicone.
FFKM O rings have excellent resistance to extreme temperatures, -10°C to +260°C. Some special compounds can operate beyond 300°C.