Tris(nonylphenyl) phosphite is widely used as a stabilizer and antioxidant in the polymer industry. It is particularly effective in preventing the degradation of polyolefins, such as polyethylene and polypropylene, during processing and long-term use. By scavenging free radicals and decomposing hydroperoxides, it helps maintain the mechanical properties and color stability of these materials. Additionally, it is employed in the production of adhesives, coatings, and elastomers to enhance their resistance to heat and oxidation. Its ability to act as a secondary antioxidant makes it a valuable component in formulations where synergistic effects with primary antioxidants are desired.