Used as a monomer in the synthesis of high-performance polymers such as polyethers and polycarbonates, 4,4'-Dihydroxydiphenyl contributes to materials with excellent thermal stability and mechanical strength. It plays a key role in the production of engineering plastics and specialty resins used in aerospace, electronics, and automotive industries. Additionally, it serves as an intermediate in the manufacture of antioxidants and UV stabilizers for polymers. Its structural rigidity enhances the glass transition temperature of resulting polymers, making them suitable for high-temperature applications.