Multiple chain termination by aromatic nitroxides in oxidation of styrene

The antioxidant activity of aromatic nitroxides in the oxidation of styrene was studied using a complex of kinetic methods in combination with quantum chemical calculations and kinetic modeling. During oxidation of styrene and its saturated analog, ethylbenzene, aromatic nitroxides terminate oxidation chains via the reaction with both alkyl and peroxyl radicals. The mechanism of the process was proposed, which explains multiple chain termination by the interaction of peroxyl and nitroxide radicals revealed in the investigation of styrene oxidation.