| Popis: |
The antioxidant action of thiophenes is shown to be due to a heterolytic decomposition of hydroperoxides effected by SO2 (H2SO4) which is liberated from the thiophene. Thus, the initiation level in an autoxidizing alkylaromatic compound (n-hexylbenzene) is decreased and the oxidation is further inhibited by phenol, the heterolysis product of the hydroperoxide. At low thiophene concentrations the inhibition is counterbalanced by the low initiation level in such a way that the oxidation continues to proceed at a constant rate. The effect of substituents, of the concentration and of added bases on the antioxidant activity of thiophenes is reported. |
