Butyl Rubber - O-Ring & Engineered Seals Division | Parker US

Material Selection Guide


BUTYL RUBBER (IIR)


Butyl (isobutylene, isoprene rubber, IIR) has a very low permeability rate and good electrical properties.

Heat resistance:

  • Up to approximately 121°C (250°F)

Cold flexibility:

  • Down to approximately -59°C (-75°F )

Chemical resistance:

  • Hot water and steam up to 121°C (250°F)
  • Brake fluids with glycol base (Dot 3 & 4)
  • Many acids (see Fluid Compatibility Tables in Section VII)
  • Salt solutions
  • Polar solvents, (e.g. alcohols, ketones and esters)
  • Poly-glycol based hydraulic fluids (HFC fluids) and phosphate-ester bases (HFD-R fluids)
  • Silicone oil and grease
  • Ozone, aging and weather resistant

Not compatible with:

  • Mineral oil and grease
  • Fuels
  • Chlorinated hydrocarbons