The antioxidant added to synthetic rubber during the synthesis process should be selected according to the synthesis process and product color. For solution-polymerized rubber, you need to choose an antioxidant that is easily soluble in the solvent used in rubber synthesis. For emulsion-polymerized rubber, you need to choose an antioxidant that can form a stable emulsion with the emulsifier used in rubber synthesis. In addition, according to the color of the product, choose pollution type or non-pollution type. type of antioxidant. Polybutadiene rubber (BR), styrene thermoplastic elastomer, isoprene rubber (IR) and other solution-polymerized rubbers used antioxidant BHT (264) in the past, and sometimes phosphite antioxidant TNP (TNPP) was used in combination. Antioxidant TNP is easily hydrolyzed, and its use is prohibited because the nonylphenol produced affects the reproductive health of organisms. Antioxidant BHT has a relatively small molecular weight and is easy to volatilize. Foreign studies believe that its many volatiles are harmful to the environment. Therefore, other phenolic antioxidants are currently used instead. The more common antioxidants are 1076 and 1520. Or use supplementary antioxidants in combination to produce synergistic effects. The phenolic antioxidant styrenated phenol is mostly used in the light-colored latex rubber, and the pollution-type amine antioxidant is used in the dark-colored rubber. Synthetic rubber antioxidants are developing in the direction of environmental protection, large molecular weight, compounding and multi-functionality. The oxidation induction period or oxidation induction temperature of raw rubber can be detected by DSC method, and the performance of antioxidants can also be investigated by thermal oxygen aging performance. Light-colored rubber products also need to investigate thermal oxygen aging resistance and yellowing resistance.