| Section2 = | Section3 = | Section7 = | Section8 = }} Propylene, also known by its IUPAC name propene, is an organic compound having the chemical formula C₃H₆. It is the second simplest member of the alkene class of hydrocarbons, ethylene (ethene) being the simplest. At room temperature and pressure, propylene is a gas. It is colorless (mercaptan, a hydrocarbon with an odor similar to garlic is sometimes added to propylene to make it more easily detectable), and highly flammable. It is found in coal gas and can be synthesized by cracking petroleum. Propylene is a major commodity in the petrochemicals industry. The main use of propylene is as a monomer, mostly for the production of polypropylene. Propylene is also used as a fuel gas for various industrial processes. It has a similar calorific value to propane, but a lower mass of combustion products, so it has a higher flame temperature. Propylene also has significantly higher vapour pressure than propane at room temperature.

• Inhalation reference exposure level
  3,000 micrograms/m³ (2,000 ppb)
• Hazard index
  Respiratory system
• Critical effects: squamous metaplasia (males and females), epithelial hyperplasia (females only), inflammation of the nasal cavity in Fischer 344/N rats (males only)

External results