Styrene-butadiene rubber (SBR) is a synthetic rubber that was developed by Walter Bock as a substitute for natural rubber in 1929. It is made of styrene and butadiene. SBR is abrasion resistant with high tensile strength and good aging stability. The elasticity and hardness can be customized by controlling the mixture ratio. SBR is a common material used for tires, flooring, carpet, and textile backings.