1-Butene is an organic chemical compound, linear alpha-olefin (alkene), and one of the isomers of butene. The formula is C4H8. 1-Butene is stable in itself but polymerizes exothermically. It is highly flammable and readily forms explosive mixtures with air. It is, however, incompatible with metal salts, fluorine and other halogens, nitrogen oxides, boron trifluoride, hydrohalic acids, and strong oxidizing agents. 1-Butene is produced either by separation from crude C4 refinery streams or from the dimerization of ethylene. It is distilled to give a very high-purity product. 1-butene is used to manufacture lots of other chemical products, such as linear low-density polyethylene (LLDPE), polypropylene resins, polybutene, butylene oxide, and butanone.