Polycarbonate
The term ‘polycarbonate’
derives from the polymer chain repeat carbonate
unit and the polymers are in effect polyester
derivatives of carbonic acid.
The starting material for polycarbonate plastics
is bisphenol A, first synthesized at the
University of Marburg, Germany, in 1905. This
dihydric phenol was used independently by Dr
Herman Schnell at Bayer, Krefeld-Uerdingen in
Germany and Dr Daniel Fox of General Electric in
the USA in 1953 to develop processes for
manufacturing the new polymer material.
Significant industrial production began in
1958 and growth in the volume and types of
application rapidly followed. Important
properties include strength, toughness, rigidity,
excellent optical and electrical insulation
coupled with heat and environmental stability.
Polycarbonate is often employed for its high
resistance to impact and is familiar as vandal
resistant glazing and the material used for CDs
since their introduction in 1982. Other important
uses include safety helmets, chocolate moulds,
casings for domestic and office equipment, baby
feeding bottles and medical equipment.
|
