Kinetics of the oxidation of methyl methacrylate in the presence of phenolic compounds

Abstract

The kinetics of the reaction of methyl methacrylate with oxygen in the presence of 2,2'-azobisisobutyronitrile has been studied at 60-70º both in the presence and absence of phenol and 2,6-di-t-butyl-p-cresol. Retarded rates are proportional to the first power of the initiator concentrations, the first power of the methyl methacrylate concentrations, and the inverse first power of the phenol concentrations. The overall activation energy of the reaction in the absence of phenol is 31.51 kcal/mole and in the presence of phenol is 41.00 kcal/mole. The mechanism is discussed in the light of the experimental results and it is inferred that termination in inhibited oxidation proceeds through hydrogen abstraction and chain transfer.