Radical initiator

In chemistry, radical initiators are substances that can produce radical species under mild conditions and promote radical reactions. These substances generally possess weak bonds—bonds that have small bond dissociation energies. Radical initiators are utilized in industrial processes such as polymer synthesis. Typical examples are halogen molecules, azo compounds, and organic and inorganic peroxides.

The sulfate radical adds to an alkene forming radical sulfate esters, e.g. ^.CHPhCH₂OSO₃⁻, that add further alkenes via formation of C-C bonds. Many styrene and fluoroalkene polymers are produced in this way.

Some radical initiators such as azo compounds and peroxides are often unstable. They are often stored cold.

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