ASTM D 1418 Designation: SBR

ASTM D 2000, SAE J200 Type / Class: AA, BA

STANDARD COLOR: Black

TRADE NAMES: Too numerous to list.

RELATIVE COST: Low

GENERAL TEMPERATURE RANGE: -50° to +212° F

Also known as Buna S, or GRS (Government Rubber Styrene), styrene butadiene is a copolymer of styrene and butadiene (see Figure 49). Though SBR’s low strength properties require the addition of reinforcing agents to make the compound stronger, SBR was widely used as the synthetic substitute for natural rubber during World War II. Like natural rubber, SBR is non oil-resistant.

SBR’s use since WWII has sharply declined, though it is still used in automobile tire production and in assorted molded rubber goods. SBR is unsuitable for some applications because the double bond in the polymer backbone invites attack by oxygen, ozone, and UV light.

SBR PERFORMS WELL IN:
• Water
• Alcohol
• Silicone oil & grease
• Automotive brake systems

SBR DOES NOT PERFORM WELL IN:
• Petroleum oils & fuels
• Strong acids
• Aromatic, aliphatic, or halogenated hydrocarbons
• Mineral oils

“SBR is used in automobile tire production and in assorted molded rubber goods.”

Figure 49