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Polycarbonate (PC) resins are tough thermoplastics usually derived from bisphenol A and phosgene. PC was commercialized in the early 1960s and is now the second-largest-volume engineering resin produced, following crystalline nylon. PC is an amorphous, very clear polymer with exceptionally high levels of impact strength and ductility, as well as inherent fire resistance and useful engineering properties over a wide temperature range. PC has good resistance to UV light, although it has a tendency to yellow with long exposure. UV stabilizers have overcome this problem to some extent. PC has very good resistance to aqueous solutions of organic and inorganic acids, salts and oxidizing agents, but limited resistance to organic solvents.
In general, polycarbonates have become established in applications that utilize a combination of properties, particularly impact resistance and/or clarity. Major markets include safety and antivandalism glazing, automotive instrument panels and lens systems, appliances and power tools, optical memory, ophthalmic lenses and lighting fixtures.The largest markets for polycarbonate resins are electrical/electronic (including computer and business equipment and optical discs), glazing and sheet usage, and the automotive industry.
The following pie chart shows consumption of polycarbonate resins by major region; these four countries/regions represent about two-thirds of global consumption:
The polycarbonate resin business is global, with two dominant producers and three other major producers. Bayer MaterialScience is the largest worldwide producer, accounting for 30% of world capacity in 2008. The second-largest is SABIC Innovative Plastics with 27%, followed by Teijin, Dow Chemical and Mitsubishi companies (Mitsubishi Chemical, Mitsubishi Gas Chemical and Mitsubishi Engineering Plastics) with 11%, 9% and 8%, respectively. Bayer, SABIC and Dow have plants in three regions—the United States, Western Europe and Asia; Teijin and Mitsubishi each have multiple plants in Asia.
Forecast growth rates for consumption vary widely by region. The fastest growth is expected in Asia, averaging almost 9% per year during 2007–2012, followed by Central and South America with 5%; Europe, Middle East and Africa at 5%; and North America at almost 4%.
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