Antioxidant

Antioxidant refers to a kind of substance that can delay or inhibit the occurrence of oxidation reaction, ensure the material does not deteriorate during storage, smooth processing and long service life. Polymer materials (including plastics, rubber, fibers, paints, etc.) often undergo performance deterioration during processing, storage, and use. Such as plastic yellowing, embrittlement, cracking, rubber sticky, hard, cracking, insulation performance, fiber product strength reduction, fading, fracture, etc., most of these phenomena are due to polymer materials and oxygen A reaction occurs that results in degradation or cross-linking. Especially in hot processing and exposure to sunlight, the oxidation rate is faster. The oxidation of the polymer is a free radical chain reaction, and the antioxidant can capture the active free radicals, generate inactive free radicals, thereby terminating the chain reaction; or decompose the products of oxidative degradation into non-free radicals. The product interrupts the chain reaction. In short, the role of antioxidants is to delay the oxidation process of polymer materials, to ensure that they can be processed smoothly and extend their service life. Antioxidant is the main body of stabilizing auxiliaries, and is widely used in polymer materials such as natural rubber, synthetic rubber, polyolefin plastic and fiber. In the petroleum industry, antioxidants prevent the auto-oxidation of hydrocarbons in oil fields, especially olefins, discoloration during storage and the formation of gelatinous materials. Antioxidants can also be used in the processing of fatty foods. In the rubber industry, antioxidants are commonly known as antioxidants. According to the mechanism of action, antioxidants have free radical inhibitors, also known as primary antioxidants (including two major series of amines and phenols), which include amines such as p-phenylenediamine, diaryl secondary amine, aldehyde amine and ketone amine. Compounds, and phenolic compounds such as antioxidants 264, 1076, 330, 1010; and peroxide decomposers, called auxiliary antioxidants (mainly thioesters such as thiodipropionate and phosphites) Large class). A general auxiliary antioxidant is used in combination with the primary antioxidant to produce a synergistic effect. In addition, antioxidants include copper inhibitors and antiozonants. Antioxidants are widely used in the processing of natural rubber, synthetic rubber, plastics, synthetic fibers, petroleum products and fatty foods. Antioxidants used in the rubber industry are commonly known as antioxidants. High efficiency, low toxicity and low price are the main directions for the development of antioxidants.