Polycarbonates (PC) are thermoplastic polymers containing carbonate groups.

 

Polycarbonates

Polycarbonate is a strong, transparent, and amorphous high-performance thermoplastic polymer. It has outstanding qualities such as moisture resistance, chemical resistance, and electrical resistance, as well as thermal stability. It is made by a step-growth polymerization technique. Furthermore, polycarbonate resins may be converted into components utilising injection moulding and extrusion processes.

Polycarbonates are strong, durable materials that are optically transparent in some grades. They are simple to work with, mould, and thermoform. Polycarbonates have a wide range of uses because to their characteristics. Polycarbonates lack a specific resin identification code (RIC) and are labelled as "Other," number 7 on the RIC list. Bisphenol A, a precursor monomer, can be found in polycarbonate products (BPA).

Carbonate esters contain planar OC(OC)2 cores that give them stiffness. The unique O=C bond is short, but the C-O bonds are more ether-like (bond distances of 1.326 in the example shown). Polycarbonate got their name because they are polymers with carbonate groups (O(C=O)O). Polycarbonates are classified as engineering plastics due to a combination of beneficial qualities such as temperature resistance, impact resistance, and optical properties.

Polycarbonate is a long-lasting material. It has a good impact resistance but a moderate scratch resistance. As a result, polycarbonate eyeglass lenses and polycarbonate exterior vehicle components are given a durable covering. Polycarbonate has properties similar to polymethyl methacrylate (PMMA, acrylic), but it is tougher and can withstand higher temperatures for longer. Thermally treated material is typically completely amorphous, making it very transparent to visible light and transmitting more light than several types of glass.

Because polycarbonate has a glass transition temperature of around 147 °C (297 °F),[8] it softens progressively above this point and flows above approximately 155 °C (311 °F). To produce strain-free and stress-free goods, tools must be kept at high temperatures, often above 80 °C (176 °F). Low molecular mass grades are simpler to work with than higher molecular mass grades, but their strength suffers as a result. The hardest grades have the largest molecular mass, but they are also the most complex to process.

Polycarbonate, unlike other thermoplastics, can withstand massive plastic deformations without splitting or breaking. As a result, sheet metal processes such as bending on a brake may be used to treat and shape it at room temperature. Heating may not be essential even for steep angle bends with a small radius. This makes it useful for prototype applications that need translucent or electrically non-conductive pieces that cannot be manufactured from sheet metal. PMMA/Acrylic, which resembles polycarbonate in appearance, is brittle and cannot be bent at room temperature.