Antioxidant is a chemical substance. When it only exists in the polymer system, it can delay or inhibit the oxidation process of the polymer, thus preventing the polymer from aging and prolonging its service life. It is also called anti-aging agent. Why do you add antioxidants to plastics and elastomers?
The effective solution to the yellowing of elastomer is to add antioxidant and ultraviolet absorber, which can effectively prevent and delay the yellowing. For the processing of engineering plastics, antioxidants can prevent some polymers (such as ABS) from thermal oxidation degradation during processing, and make the molding process go smoothly. The amount of antioxidant added is generally only 0.1-0.5 parts.
Classification of antioxidants added to plastics and elastomers:
Classification of antioxidants, one is the main antioxidant: antioxidant that traps oxidative free radicals, mainly phenol-blocking; Main sterically hindered phenol, antioxidant 1010. Antioxidant 1076 belongs to this category. It can capture free radicals generated during the degradation of plastics, and play an antioxidant role for a long time.
One is the auxiliary antioxidant: decomposing hydroperoxides, mainly phosphites and thioesters. Auxiliary resistance-phosphite and thioester, antioxidant 168 belongs to auxiliary resistance of phosphite, which can achieve antioxidant purpose by decomposing peroxide generated by further degradation of plastics, mainly providing hot processing stability; The main resistance plus auxiliary resistance can produce synergistic effect.