Polycarbonate is a tough sheet material that is transparent and thermoplastic. Polycarbonate is often used in safety goggles, CD cases, car windshields, sunroofs and bullet-proof windows.
Produced by linking together bisphenol A (BPA) molecules from two different monomers, the process of polycarbonate production can be divided into three stages. First, the bisphenol A (BPA) molecules are mixed with an equal amount of di-2-ethylhexyl phthalate (DEHP). Secondly the mixture is heated up to 200°C in order to melt it down into a viscous liquid mixture. Finally, the mixture is poured into molds at -20°C to produce super-cooled pellets that are then heated and stretched to produce sheets.
The production of Polycarbonate resins involves the addition of monomers. Polycarbonates are produced by adding the bisphenol A (BPA) and di-2-ethylhexyl phthalate (DEHP) monomers in an acid solution. The acid solution facilitates the ring opening polymerization in which new linkages are formed in successive steps. The product formed through this reaction is called bis(chloroformate). In order to achieve the production of polycarbonate polymer it is necessary to remove the hydrochloric acid in two different steps. The first step is done by treating it with hydrochloric mixtures and distillation in a vacuum. The second step involves treating the material with benzene and distillation at elevated temperatures.
The product that is produced from this process contains monomers of both bisphenol A (BPA) and di-2-ethylhexyl phthalate (DEHP). This product is then separated into two parts, one part contains only di-2-ethylhexyl phthalate (DEHP) molecules, while the other part contains only bisphenol A (BPA) molecules. The two monomers are then added in an acid solution that is able to melt the polymerized molecules. The more the two monomers are mixed, the more they can form homo- and copolymers and complex compounds.
It can be melted before it is poured into molds to create super-cooled pellets. After the pellets are placed into a heated, high temperature vacuum, it reaches a temperature of 0°C. In order to obtain sheets, these pellets are stretched and heated in a mold. This heating process creates polycarbonate material that is transparent and thermoplastic. Polycarbonate is a plastic polymer which is strong, heat resistant, and transparent. It can be used for a variety of products including water bottles, CD/DVD cases, eyeglasses, compact discs and DVDs. Polycarbonate is typically found in the form of clear sheets that are used in the fabrication process.
Polycarbonates belong to a class of plastics called thermoplastics which means they soften when heated and harden when cooled. Polycarbonates are used to form shatter-resistant items such as baby bottles because they have high impact strength properties at low temperatures but do not crystallize or become brittle at high temperatures.
Polycarbonates are synthetic and can be described chemically as polymers that have the repeating structure “–O–(C=O)–” where C=O is the carbonyl group. The reaction was discovered in 1933 by a Polish chemist, Kazimierz Funk. The use of carbonates for this reaction was suggested by an American chemist, George W.Gray, but Funk developed the idea into a practical synthesis of the material. Its uniqueness is that it can convert to glass at temperatures.
Polycarbonate is a synthetic material that has many similarities to glass. It has the same density and tensile strength when compared to glass, however, it cannot be cut with a knife or heated to temperatures exceeding. For this reason, polycarbonates are typically used at room temperature or below. Polycarbonate is approximately 70% cheaper than glass and comes in various types of materials including two-way optical lenses such as sunglasses. This material is also approximately half the weight of glass meaning it can be molded into any shape without using any additional components. The material is transparent because it allows visible light to pass through it.
Polycarbonate is used for the production of eyeglasses because of its impact resistance. The lenses are typically made out of polycarbonate because it is scratch-resistant and durable at low temperatures. It can also be molded into any shape and has a relatively high level of transparency making it ideal for use in this product.