Phosphite Antioxidant

https://www.uvabsorber.com/products/phosphite-antioxidant/

Secondary antioxidants, such as phosphite antioxidant and thioethers, decompose hydroperoxides into non-radical, non-reactive, and thermally stable products. Therefore, auxiliary antioxidants are also called hydroperoxide decomposers. Phosphites and thioethers antioxidants are widely used hydroperoxide decomposers. Phosphites are most effective at the high temperatures of melt processing operations, while thioethers work best in the solid phase at long-term use temperatures. Secondary antioxidants are used together with primary antioxidants to increase the stability of polymers.