Anionic polymerisation

(Addition polymerisation)

Treatment of cold THF (Tetrahydrofuran) solution of styrene with 0.001 equivalent of n butyl Lithium causes an immediate polymerisation.
This polymerisation is an example of anionic polymerisation.
Chain termination occurs when reacted with carbon dioxide or water or chain transfer seldomly occurs.
Only the monomers having anion stabilizing groups such as phenyl, carbonyl and cyano groups act as good substrates for anionic polymerisation.
The species initiating anionic polymerisation are alkali metals, alkali amides, alkyl lithiums and other electron sources.

Anionic polymerisation of styrene.

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