Explanation

materials (especially alkyl based rubber materials) are under the combined action of heat and oxygen. The appearance and physicochemical properties change over time. Appearance includes surface of materials hardening, cracking or softening, sticky, materials geometric dimension changes; Physical and chemical properties, including chemical composition, density, hardness, tensile strength, viscoelasticity and electrical properties, will also change. The hydrocarbon bond of macromolecule materials will form peroxide radical under the action of high temperature and oxygen, and free radicals can trigger a series of chain reactions such as branching, crosslinking, cyclization, carbonylation, etc. of alkyl, double bond, carbonyl, etc. of adjacent molecular chains, which will change the structure of molecular chains. In the use of materials, it is often necessary to add phenol, aromatic secondary amine, etc. as antioxidant. Capture free radicals generated under hot oxygen conditions. The phenomenon of thermal oxidative aging of materials can usually be studied through simulation experiments in the oven.

Classification