Isobutylene is a colorless gas with a sweet odor, primarily used in the production of synthetic rubber and fuels. It is an important building block in the chemical industry, often polymerized to create polyisobutylene, which is used in adhesives, sealants, and coatings. Isobutylene is produced from petroleum refining and can also be derived from natural gas. It is classified as an alkene, meaning it contains a carbon-carbon double bond, which makes it reactive and useful in various chemical reactions. Safety precautions are necessary when handling isobutylene due to its flammability.