Reactions of antioxidants with molecular oxygen. Part I. 2,2′-methylene-bis(4-methyl-6-tert-butylphenol) in silicone matrix

The reaction of 2,2′-methylene-bis(4-methyl-6-tert-butylphenol) stabiliser with oxygen was studied in an inert substrate at 80-120 °C temperature under 0.02-3.0 MPa oxygen pressure ranges. UV/VIS spectrophotometry and Gel Permeation Chromatography were used to follow the antioxidant consumption and the formation of oxidation products. A simplified mechanistic model of stabiliser oxidative transformation was proposed and corresponding kinetic parameters were determined and compared with the kinetic values obtained by other authors.