Polycarbonates

Polycarbonate is an amorphous thermoplastic material discovered in 1953 by Schnell, Bottenbruch and Krimm, three researchers working for Bayer AG, and General Electric's D ^r Daniel W. Fox. First marketed in 1958, it currently consumes 1,200,000 tonnes a year worldwide.

Polycarbonate is a polymer derived from the polycondensation of bisphenol A and a carbonate or phosgene (carbonyl chloride). This manufacturing process is the most common and is still the most widely used by the main producers, but regulations and applications are directing the technology towards a purer, cleaner resin in terms of residual phosgene via the melt process.

The polycarbonate resins produced are either used directly or granulated with the appropriate additives, depending on the properties required for a specific application. The use of these additives in formulation is increasingly regulated in terms of health and safety.

The advantages of polycarbonate are that it's a transparent material with very good impact resistance, heat resistance allowing use up to 120 ˚C and excellent aesthetics thanks to its transparency. However, its sensitivity to chemical agents and ultraviolet light limits its use.

Recent years have seen the emergence of new and growing applications, particularly in the communications field, such as compact discs and versatile digital discs.