Who invented epoxies and why?

Originally used for dental fixtures, epoxies were created in the 1930s by two scientists, Dr. Pierre Castan in Switzerland and Dr. Sylvan Greenlee in the United States. The first epoxies were amber-coloured solids but soon became widely available as adhesives. Today, more than 50 different substances known as epoxy resins are available and used in a wide range of different applications.