Antioxidants are a class of chemicals that, when present in polymers When only a small amount exists in the system, it can delay or inhibit the oxidation process of the polymer, thereby preventing the aging of the polymer and extending its service life. It is also called an “anti-aging agent”.
1. The role of antioxidants:
In every stage of the polymer life cycle, that is, during its survival, storage, processing, and use , will cause oxidation due to themselves or external factors, resulting in the decline or loss of the performance of the polymer and its products. This is also known as the aging of polymer materials. Adding antioxidants is an effective means to delay material aging. Antioxidants are chemical additives that can inhibit and delay the oxidation and degradation of polymer materials. Its mechanism of action is complex, and its main functions are as follows:
1. Block the polarity of the degradation chain reaction
2. Decompose hydroperoxides. According to this mechanism, it can be divided into chain terminators, peroxide decomposers, and metal passivators. Among them, chain terminators are customarily called primary antioxidants, and peroxide decomposers are called auxiliary antioxidants. According to the structure, it can be divided into hindered phenols, amines, phosphites, thioesters and other categories.
2. An ideal antioxidant should meet the following requirements:
1. High antioxidant degradation efficiency.
2. Good compatibility with basic materials.
3. No adverse effects on the basic physical and mechanical properties of the product.
4. High thermal stability and good heat resistance.
5. Low volatility, moderate diffusion and migration, and good solvent extraction resistance.
6. No adverse reactions with other additives.
7. Non-toxic, non-irritating to the human body, no odor, and low pollution.
8. Cheap and easy to buy
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