Reactions of dibenzoyldiazene. Part 1. Cycloaddition and the inhibition and retardation of vinyl addition polymerizations

Abstract

The cycloaddition of dibenzoyldiazene to a selection of monomers with electron-rich vinyl groups has been shown to compete with its capability as an inhibitor of their polymerization by a free-radical mechanism. Cycloaddition to monomers with electron-deficient vinyl groups does not occur, and dibenzoyldiazene acts solely as a retarder of their polymerization. Kinetic mechanisms compatible with the experimental observations are proposed.