Stable Radicals of Inhibitors of Oxidative Processes

Abstract

In the oxidation of polymers, as was shown in Chapter I, the active centers that carry the oxidation chains are radicals of the type of RO^˙ and RO ^˙₂ . Such radicals can be determined in the substance being oxidized by the EPR method only in exceptional cases [1], since the rate of their destruction is very great, and hence their concentrations are small and lie below the limit of sensitivity of the modern EPR spectrometers. However, if substances capable of reacting rapidly with active radicals and thereby forming stable radicals, incapable of intensively continuing the oxidation chain, are added to the substrate being oxidized, then the concentrations of such radicals can be determined by the EPR method, and their structures can also be identified [2].