The Autoxidation of Rubber and Mechanisms of Protection against Oxygen
Abstract The autoxidation of ethylenic hydrocarbons has been the object of various investigations, and various authors, among whom Engler and Stephens in particular might be mentioned, have studied the part played by peroxides. Up to 1936 it was generally believed that structurally these peroxides represent the fixation of one molecule of oxygen on the double bond. About this time, however, Criegee on the one hand, and Hock and Sehrader on the other, published papers almost simultaneously on the preparation and constitution of cyclohexene peroxide, in which they demonstrated that the latter can exist in the form of a hydroperoxide.Later these investigators offered further proof in favor of this view by extending the reaction to other hydrocarbons. These studies led to the important conclusion that ethylenic hydrocarbons have two sensitive points: the double bond itself, and the carbon in α-position to this double bond; hence there are two forms of the peroxide, the first of which retains its unsaturated character.