Polycarbonate materials have a balance of useful features which include high temperature resistance, impact resistance and optical properties position polycarbonates between commodity plastic materials and engineering materials.
Polycarbonate is a very tough material. Although it offers extraordinary impact-resistance, it has minimal scratch-resistance and thus a hard coating is often applied to polycarbonate eyeglasses as well as polycarbonate exterior vehicle components. The characteristics of polycarbonate are like those of Acrylic PMMA materials, and yet polycarbonate is going to be stronger, it is usable in a wider temperature range and is a bit more expensive. This plastic polymer is highly transparent to visible light and has better light transmission characteristics than several types of glass.
Polycarbonate has a glass transition temperature of about 150 °C (302 °F), so it softens slowly above this point and flows above about 300°C (572 °F). Tools need to be held at high temperatures, generally above 80 °C (176 °F) to make strain- and stress-free products.
Unlike almost all other thermoplastics, polycarbonate can undergo large shape changes without cracking or breaking. For that reason, it is sometimes processed and formed cold using sheet metal techniques, such as forming bends with a brake. For even sharp angle bends having a tight radius, no heating is usually necessary. This makes it attractive prototyping applications where transparent or electrically non-conductive parts are important, which cannot be made from sheet metal. Be aware that PMMA/Plexiglas, that is certainly similar in looks to polycarbonate, but it is brittle and can't be bent unless it is heated.
The light weight of polycarbonate, in contrast to glass, has led to development of electronic touch screens that replace glass with polycarbonate, for use in mobile and portable devices. Such displays include newer e-ink and several LCD screens, though CRT, plasma screen and other LCD technologies which still require glass for its higher melting temperature and its ability to be etched with finer detail.
Other types of items manufactured from Polycarbonate include durable, lightweight luggage, MP3/digital audio player cases, computer cases, high impact riot shields, instrument panels, and blender jars. Many toys and hobby items are manufactured from polycarbonate parts, e.g. fins, gyro mounts, and flybar locks for use with radio-controlled helicopters.
For use in applications exposed to weathering or UV-radiation, a special surface treatment maybe needed. This can be a coating (e.g. for improved abrasion resistance), or perhaps the coextrusion for enhanced weathering resistance.
The Makrolon Polycarbonate is a thermoplastic that at the beginning, starts as a solid plastic material in the form of small pellets. In a manufacturing process called injection molding, the pellets are heated until they melt. The melted liquid polycarbonate is then rapidly pushed into molds, compressed under high pressure and cooled to form a finished product in a matter of minutes.
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