A polycarbonate (PC) resin is a thermoplastic, a polymer that liquefies when heated and then creates a glassy structure when cooled. It is used in a variety of applications that call for high-stress resistance as well as resistance to heat. Polycarbonate resin can be seen in the creation of compact discs, plastic car parts, eye wear, and bulletproof glass. Most polycarbonate resins are derived from the condensation polymerization of phosgene and bisphenol A (BPA).
The process of condensation polymerization to create a polycarbonate resin usually takes place by creating a reaction between two monomers, which are small molecules or atoms. The reaction takes place and leaves a polymer, in this case polycarbonate resin, that has both a carbonate group containing a carbon molecule and three oxygen molecules, and a by-product of small water molecules. When combining phosgene and BPA, the process is catalyzed by adding sodium hydroxide to the BPA to begin the process.
Polycarbonate resin, the final polymer that is created, has a very high tolerance to stress and can be heated to high degrees without breaking. This creates a strong substance that is very malleable, unlike other thermoplastics, which are often brittle and break if stretched or stressed too much. A big advantage to this is that it can be built to specification without having to have a mold or press created, making it invaluable in the creation of initial prototypical designs.
The primary use for polycarbonate resin is in the electronics field because makes a great insulator and won’t melt at high temperatures. In addition to the electronics field, it is widely used in materials used for construction, such as dome lights. Since it can be made in sheets and using injection molds, it can be mass-produced to make a variety of items including compact discs to advertising signs. It also has a wide variety of uses in cars and aircraft because not only is it smooth, but it can also be transparent.
One shortcoming of polycarbonate resin is that it’s easy to scratch. When used to make eyewear or any other transparent material that is subject to scratching, it needs to have an extra coating put on top to protect it. With lamination, it is used to create bullet-proof glass.
The most notable problem with polycarbonate resin is the use of BPA. Many PC resin products produced are made with BPA, such as water bottles and storage containers. BPA has been found to be an endocrine disrupter, which means it can cause a variety of issues that the endocrine system effects, such as birth defects, cancer, and neurological disorders. Despite the associations, attempts to ban or limit the use of BPA have been met with mixed results across the globe.