Antioxidant Behavior in Bulk Oil: Limitations of Polar Paradox Theory

The polar paradox theory that explains the efficacy of antioxidants as affected by their polarity and that of the medium involved was re-evaluated. For the first time, the effect of concentration on validity of the polar paradox theory was investigated using four pairs of polar and nonpolar representative antioxidants in bulk oil. A model on antioxidant behavior in response to their polarity is proposed.