Polymerization with Azo Compounds as Initiator

The yield of initiating radicals is, however, generally smaller than would be expected. In the case of AIBN this is because a certain amoxmt of tetramethyl-succinic acid dinitrile is formed by combination of the primary radicals, while some methacrylonitrile and Eo-butyronitrile are formed by disproportionation of the primary radicals. Azo compounds are especially suited as initiators for polymerization in bulk or in organic solvents. 

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