Antioxidants are the core anti-aging agents for plastics, which eliminate free radicals, decompose hydrogen peroxides, passivate metal ions, block oxidative degradation, avoid plastic discoloration and brittleness, and extend the service life. For example, adding antioxidants to PP outdoor products can extend the service life from 3 months to 3-5 years. The mainstream types are divided into four categories: hindered phenols (such as 1010), low toxicity and universal, suitable for PE/PP/PET; Phosphorous esters (such as 168) are resistant to high temperatures and are often compounded with hindered phenols; Sulfides such as DLTP are efficient at low temperatures and suitable for polyolefins; Targeted metal ion passivators prevent catalytic degradation. In terms of application, PE agricultural film uses 1076+DLTP, PET beverage bottles add 1010+168, and PP meal boxes choose low migration 1010. The current upgrade towards high molecular weight, bio based, and multifunctional directions is the key guarantee for the long-term durability of plastics....