Antioxidant is a chemical product. When its content in the polymer system is small, it will delay or inhibit the polymer oxidation process, prevent polymer aging and prolong its service life. For engineering plastics processing, antioxidants can be Prevent thermal oxidative degradation of certain polymers during processing, so that the molding process can proceed smoothly. Add antioxidants-usually this is the case.

The ideal antioxidant conditions required are: good compatibility with the resin, no precipitation, and good processing performance. Does not volatilize or decompose at the polymer processing temperature. Good extraction resistance, insoluble in water and oil, and the color itself should be colorless or pale. The product is cheap, non-toxic and non-toxic. What is the antioxidant mechanism? In fact, no antioxidant can fully meet these conditions. Therefore, in practice, additives of different lengths should be selected according to the types, uses, and processing methods of engineering plastics, and used in conjunction to achieve synergistic effects. With the development of the engineering plastics industry, the application of antioxidants has become increasingly widespread, and the demand has continued to increase. Currently, they are mainly used in engineering plastics such as polyamide, formaldehyde, and ABS. Studies on the thermal oxidation mechanism of polymers have shown that unstable free radicals and peroxides produced by heat-resistant oxidation are the main reasons for the degradation of polymer performance. The mechanism of action of antioxidants is to terminate free radicals and decompose peroxides. Contains a series of amines and phenolic compounds. Among engineering plastics, phenols are the main ones. It has strong antioxidant effect and can inhibit the free reaction of different free radicals. A kind of hydroperoxide decomposer that destroys the structure of peroxygen, called auxiliary antioxidant, mainly contains thioester and phosphorous acid, and is often used together with the main antioxidant.