NEW THERMOSETTING EPOXY RESINS BASED ON SOME BIS PHENOLS

Polymers are long-chain molecules that contain tens of thousands of monomers. For this reason, polymers are called macromolecules. Examples of naturally available polymers are cellulose, cotton, starch, wool, proteins, and silk. The synthetic polymers are polystyrene, polyethylene, and nylon. The beginning of polymer science may be traced back to the mid-nineteenth century. Charles Goodyear in 1830 succeeded in transforming the sticky latex of natural rubber into a useful elastomer for tire use. Christian F. Schonbein in the year 1847 produced cellulose nitrate out of cellulose-nitric acid reaction. Leo Hendrik Baekeland in 1907 produced Bakelite (phenol-formaldehyde resin). Glyptal (unsaturated-polyester resin) was developed as a protective coating resin by General Electric in 1912. In 1930, researchers at DuPont in the USA produced more exotic materials like nylon and Teflon. In 1938, polystyrene and in 1939 polyethylene were prepared by scientists at ICI in England