Butadiene, C 4 H 6 , exists in two isomeric forms: 1,3‐butadiene and 1,2‐butadiene. 1,3‐Butadiene is a commodity product of the petrochemical industry. Elastomers consume the bulk of 1,3‐butadiene, led by the manufacture of styrene–butadiene rubber (SBR). 1,3‐Butadiene is manufactured primarily as a coproduct of steam cracking to produce ethylene in the United States, Western Europe, and Japan. However, in certain parts of the world it is still produced from ethanol. The other isomer, 1,2‐butadiene, has no significant current commercial interests. 1,3‐Butadiene is a noncorrosive, colorless, flammable gas at room temperature and atmospheric pressure. It has a mildly aromatic odor. It is sparingly soluble in water, slightly soluble in methanol and ethanol, and soluble in organic solvents like diethyl ether, benzene, and carbon tetrachloride. The conjugated double bonds of 1,3‐butadiene allow a large number of reactions at both the 1,2‐ and 1,4‐positions. These reactions include addition, hydrogenation, oxidation, Diels–Alder, oligomerization, and polymerization reactions. Many of these reactions produce large volumes of important industrial materials. Butadiene reacts with a large number of chemicals, has an inherent tendency to dimerize and polymerize, and is toxic. Therefore, specific handling, storage, and shipping procedures must be followed. U.S. shipments of butadiene, which is classified as a flammable compressed gas, are regulated by the Department of Transportation. Short‐term exposure to high concentrations of butadiene may cause irritation to the eyes, nose, and throat. Dermatitis and frostbite may result from exposure to the liquid and the evaporating gas. In several epidemiological studies, elevation in mortality was observed for small subgroups and tumor types. Updated exposure limits are given. Butadiene is used primarly in polymers. Other uses are given.

Butadiene, C 4 H 6 , exists in two isomeric forms: 1,3‐butadiene \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}${{\rm{CH}}{_{2}}{\raise1pt\hbox{$\Relbar \kern-4pt{\Relbar}$}} {\rm{CH}}{\relbar \kern-5pt{\relbar}\kern-7pt{\relbar}}{\rm{CH}}{\raise1pt\hbox{$\Relbar \kern-4pt{\Relbar}$}} {\rm{CH}}{_{2}}}$\end{document} , and 1,2‐butadiene, \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}${{\rm{CH}}{_{2}}{\raise1pt\hbox{$\Relbar \kern-4pt{\Relbar}$}} {\rm{C}}{\raise1pt\hbox{$\Relbar \kern-4pt{\Relbar}$}}{\rm{CH}}{\relbar \kern-5pt{\relbar}\kern-7pt{\relbar}}{\rm{C}}{_{3}}}$\end{document} . 1,3‐Butadiene is a commodity product of the petrochemical industry. Elastomers consume the bulk of 1,3‐butadiene, led by the manufacture of styrene–butadiene rubber (SBR). 1,3‐Butadiene is manufactured primarily as a coproduct of steam cracking to produce ethylene in the United States, Western Europe, and Japan. However, in certain parts of the world, eg, China, India, Poland, and the former Soviet Union, it is still produced from ethanol. The other isomer, 1,2‐butadiene, has no significant current commercial interests. 1,3‐Butadiene is a noncorrosive, colorless, flammable gas at room temperature and atmospheric pressure. It has a mildly aromatic odor. It is sparingly soluble in water, slightly soluble in methanol and ethanol, and soluble in organic solvents like diethyl ether, benzene, and carbon tetrachloride. The conjugated double bonds of 1,3‐butadiene allow a large number of reactions at both the 1,2‐ and 1,4‐positions. These reactions include addition, hydrogenation, oxidation, Diels‐Alder, oligomerization, and polymerization reactions. Many of these reactions produce large volumes of important industrial materials. Butadiene reacts with a large number of chemicals, has an inherent tendency to dimerize and polymerize, and is toxic. Therefore, specific handling, storage, and shipping procedures must be followed. U.S. shipments of butadiene, which is classified as a flammable compressed gas, are regulated by the Department of Transportation. Short‐term exposure to high concentrations of butadiene may cause irritation to the eyes, nose, and throat. Dermatitis and frostbite may result from exposure to the liquid and the evaporating gas. In several epidemiological studies, elevation in mortality was observed for small subgroups and tumor types. Interpretation of these findings is still incomplete.