C2H2Cl2

C2H2Cl2 refers to a class of chlorinated hydrocarbons known as dichloroethenes. These compounds contain two carbon atoms connected by a carbon–carbon double bond, with two chlorine substituents and two hydrogens in total. There are two main structural isomer families: 1,1-dichloroethene, CH2=CCl2 (vinylidene chloride), and 1,2-dichloroethene, CHCl=CHCl, which exists as cis and trans forms. The isomers differ in structure, reactivity, and physical properties, including boiling points and volatility.

Production and uses: Dichloroethenes are produced commercially by chlorination of ethene and related processes. 1,2-Dichloroethene is widely used as a solvent and as a chemical intermediate in the manufacture of dyes, resins, and specialty solvents. 1,1-Dichloroethene is a key monomer for polyvinylidene chloride (PVDC), a polymer used in food packaging for its barrier properties against moisture and gases.

Physical properties and hazards: These compounds are typically colorless and volatile liquids at room temperature. They can be toxic and may irritate the eyes, skin, and respiratory tract. They are flammable and should be handled with appropriate safety precautions. Environmental concerns and potential health risks have led to regulatory controls and specific handling and disposal guidelines in many jurisdictions.