EVALUATION OF SOME ORGANIC-COMPOUNDS AS ANTIOXIDANTS IN RUBBER

Three different classes of organic compounds, namely triazole, oxazoli ne and p-phenylenediamine derivatives, were synthesized and investigat ed in natural rubber and styrene-butadiene rubber mixes and vulcanizat es. It was found that the efficiency of triazole derivatives increased with the introduction of electron withdrawing substituents in the par a position of the benzene ring. The only exception is the p-amino deri vative which shows a higher efficiency relative to other substituents. In contrast, it was found that the efficiency of p-phenylenediamine d erivatives increased with the increasing inductive effect of the subst ituents. A correlation between the Hammet constant and the efficiency of triazole derivatives was established. (C) 1997 Elsevier Science Lim ited.