STYRENE BUTADIENE RUBBER (SBR): BUNA S MATERIAL
SBR is probably better known under its old names Buna S (Buna material) and GRS (government rubber styrene). It was first produced under government control between 1930 and 1950, which was used as a replacement for natural rubber. The basic monomers are butadiene and styrene, with styrene content approximately 23.5%. About one third of the world output of SBR is used in tire production. SBR is mostly used in seals for non-mineral oil based brake fluid applications. Its modern usage is external to the sealing industry. Therefore, it’s mainly used for automobile tires and conveyor belts.
Both o-rings and gaskets can be made from Buna materials.
Names: Styrene Butadiene, Buna S, SBR, GRS
Compound Info | |
ASTM D1418 Designation | SBR |
ASTM D2000/SAE J200 Type, Class | AA, BA |
Hardness (Shore A) | 40-90 |
Color | black |
Thermal Properties | |
Min Temp. | -50°F (-45°C) |
Max Temp. | 212°F (100°C) |


Chemical Resistance
Water, alcohol, glycol, and certain ketones (acetone)
Non-mineral oil based brake fluid
Silicone oil and grease
Diluted water solutions, weak acids

NOT Compatible
Mineral oils
Petroleum greases and fuels
Aliphatic hydrocarbons (benzene, toluene, xylol)
Chlorinated hydrocarbons - such as chloroform, trichlorethylene, carbon tetrachloride
Oxidizing media like nitric acid, chromic acid, hydrogen peroxide, chlorine, bromine
Disclaimer: These are general guidelines only. All materials should be tested in your application.