Styrene Butadiene latex is a polymer emulsion composed of two hydrocarbon monomers, styrene and butadiene. Styrene is derived from reacting benzene and ethylene; at room temperature it is a colorless oily liquid with a sweet odor. Butadiene is a byproduct of ethylene production and is a colorless gas with a faint odor of gasoline.
Using these building blocks, in a ratio of approximately 25% styrene, 75% butadiene, produces a styrene butadiene rubber (SBR), an elastomeric co-polymer widely used as an alternative to natural rubber. SBR is found in products as diverse as tires and carpet backing.
In contrast, styrene butadiene latex is made by the polymerization of these monomers at higher temperatures resulting in a crosslinked SB latex copolymer emulsion, often referred to as X-SBR. The ratio of styrene to butadiene can be varied broadly and strongly influences end-use properties.