Abstract
In a previous publication the influence of vulcanization by sulfur and sulfur compounds on the oxidizability of rubber was shown. The most important conclusion was that, in principle, the higher the proportion of combined sulfur, the greater is the oxidizability. However, with very high proportions, the activity of the sulfur changes, i.e., above a certain upper limiting range, the oxidizability tends towards a plateau, whereas below a lower limiting range the oxidation curve passes through a minimum. After having obtained these results, it seemed to be of interest to complete the investigation by studying the effects of vulcanization by agents other than sulfur on oxidizability. In the present work we have examined vulcanization by nitro compounds and peroxides, taking as examples m-dinitrobenzene, trinitrobenzene and benzoyl peroxide. This domain of rubber chemistry has been relatively little explored and certain points either have not received final confirmation or have even led to contrary conclusions. Accordingly it seemed useful to review from a purely objective point of view what has been done on this subject.