Polycarbonate (PC) resins are tough thermoplastics with major markets in the electrical/electronic sectors such as computer and business equipment and optical discs, glazing and sheet products and in the automotive industry. Other uses include safety helmets and shields, housing components, household appliances, water cooler bottles, lighting fixtures, sporting goods, and aircraft and missile components.
Polycarbonate is a very clear polymer with exceptionally high levels of impact strength and ductility, as well as inherent fire resistance and good resistance to UV light. It also has good resistance to aqueous solutions of organic and inorganic acids, salts and oxidising agents, but limited resistance to organic solvents.
Polycarbonate can be blended or alloyed with other resins such as polybutylene terephthalate (PBT) and acrylonitrile-butadiene-styrene (ABS) to tailor price/performance properties to specific end uses. PC/PBT alloys were used by the automotive industry at one time in front and rear bumpers but thermoplastic elastomers are now used. PC/ABS alloys are used mainly in housings for office machines. Other materials that can be blended or alloyed include thermoplastic polyurethane, acrylate-styrene-acrylonitrile and styrene-maleic anhydride copolymers.
The optical media segment which includes CDs and DVDs has recorded the strongest growth with rates around 35%/year from 1996-2000, slowing to 10%/year in the 2001-2005 period. However, its future growth rate will slow significantly and then start to decline as CDs and recordable CDs are replaced by MP3/MP4 players, high internet bandwidth and USB drives. Recording industry trade group IFPI predicts that one quarter of global music sales will be downloaded from the internet by 2010.
Sony’s Blu-Ray high definition DVD is expected to boost PC demand although downloading via the internet, cable and satellite may impact these discs. Media consultants are now expecting a short-lived growth spurt for high definition DVDs before video on demand via the internet and cable and satellite television services overtake the Blu-Ray technology. However, this may allow a more orderly decline in the overall optical media market.
Growth is still expected in other sectors such as alloys used in automotive and electronic products, cell phones, TVs, business equipment and sheet and construction products.
Opportunities in automotive glazing
Automotive glazing offers potentially strong growth opportunities for polycarbonate. While polycarbonate is being used in headlamp and tailgate lenses, roof modules and fixed side windows in cars and trucks, there has been strong resistance from the automobile manufacturers in the more general replacement of glass. Polycarbonate has replaced glass on windscreens for motorcycles due to its light weight and safety factors.
One of the problems is the poor scratch resistance of polycarbonate although PC producer Bayer claims that multi-layer products have been developed that overcome this problem. The higher cost compared to glass could be another limiting factor although polycarbonate does offer weight savings, broader design options and easier handling that could bring efficiencies on the automotive production line.
Bayer predicts that global polycarbonate demand for automotive glazing could reach between 100,000 tonnes and 200,000 tonnes by 2014. Applications are expected to widen into back lights and rear windows in truck cabins, moveable side windows and vehicle top applications.
Global polycarbonate demand had been growing at 7-8%/year. US-based consultants CMAI estimates that total global polycarbonate demand in 2008 was around 3.27m tonnes.
Slower global growth predicted
Demand has been hit by the economic crisis impacting particularly the construction and automotive sectors. CMAI expects global demand will start to recover again in 2011. Meanwhile, Bayer is predicting slower growth at around 5%/year between 2009 and 2015 as the key optical media market slows.
The downturn in demand has resulted in a number of projects being delayed or postponed indefinitely. However, CMAI still expects the growth in capacity to outstrip demand growth. The majority of the new capacity is planned in Asia and there is a large 260,000 tonnes/year plant in Saudi Arabia due on-stream in late 2011. CMAI predicts global operating rates to fall to the low 70s% by 2012.
Asia Pacific already is the largest polycarbonate market worldwide, representing more than half of the global market. Bayer estimates that China alone will account for 40% of the global market in the next two-to-three years. Estimates from PC producers put growth rates in China up to 10%/year.
The US market had been growing at 5%/year but a prolonged weakness in the US housing and automotive markets will have impacted demand. While growth is slowing in the optical media sector, long-term growth is still expected in other sectors such as alloys used in automotive and electronic products. With higher fuel economy goals mandated in the US, automotive glazing offers potentially strong growth for PC.
Several US retailers have removed polycarbonate food and beverage containers from their shelves due to concern that small amounts of bisphenol-A (BPA) can be released from the polycarbonate bottle. The US government’s National Toxicology Program has said there is limited evidence that low doses of BPA can cause health problems and reproductive defects in humans. However, the impact on polycarbonate demand is expected to be small as total packaging applications only account for 3% of overall demand.
US producers have relied strongly on the export markets with exports estimated by the US International Trade Commission at 406,000 tonnes in 2008, equivalent to 42% of domestic capacity. While exports grew by 2% in 2008 compared to 2007, the figures hide a sharp decline in the last part of the year. Exports in early 2009 were down by a half. In the longer term, US exports could be impacted by new capacity in Asia and the Middle East.
Updated: May 2009. Sources: ICB Chemical Profiles, 18 May 2009 and 5 May 2008; CMAI 2008 World Petrochemical Conference, 25-26 March 2009, Houston, Texas.
Polycarbonate
Process Technologies
The first aromatic polycarbonates were prepared in the late 1890s by reacting hydroquinone or resorcinol with phosgene in pyridine but the crystalline polymers produced were brittle and difficult to process. In 1941, PPG introduced a crosslinked resin prepared by a peroxide initiated radical polymerisation of the bisallyl carbonate of diethylene glycol. The colourless, transparent plastic was the first commercially available polycarbonate.
More about Polycarbonate Process Technologies
Search for
Polycarbonate
Suppliers
If you are sourcing
Polycarbonate
products and services, use ICIS search for fast and accurate results. ICIS search
is the search engine dedicated to the chemical industry – we show you only relevant
results -
search now.