4,4′-Dihydroxydiphenyl sulfide, also known as 4,4′-thiobisphenol, is an organic compound characterized by two phenolic hydroxyl groups attached to a diphenyl sulfide core. This compound exhibits significant antioxidant and antimicrobial properties, making it valuable in various industrial applications. Its unique chemical structure allows for extensive use in polymer chemistry, particularly in the synthesis of epoxy resins and other thermosetting materials. Due to its ability to enhance thermal stability and mechanical properties, 4,4′-dihydroxydiphenyl sulfide plays a crucial role in the development of durable materials used across multiple sectors, including electronics and coatings.