Used primarily as a stabilizer in polymer systems, particularly in polyolefins, to prevent degradation caused by heat and light. Its bulky tert-butyl groups provide steric hindrance, enhancing resistance to oxidation during processing and extending the lifespan of plastic materials. Also employed in specialty formulations where high thermal stability is required, such as in adhesives, lubricants, and resins. Additionally, it serves as an intermediate in the synthesis of other fine chemicals and pharmaceuticals due to its stable aromatic backbone and reactive carboxylic acid functionality.