Issue Date: June 22, 2009
No polymer has enjoyed the kind of growth that polycarbonate has had in recent years. In the 1990s and early 2000s, the plastic sometimes enjoyed double-digit gains, spurred by growing use of compact discs and DVDs. But as concerns over polycarbonate’s building block, bisphenol A (BPA), spread and optical media discs become obsolete, the fortunes of polycarbonate producers are changing. Now they are trying to develop new applications to keep polycarbonate’s winning streak going.
Polycarbonate was first developed by General Electric and Bayer in the 1950s. It is commonly made by polymerizing BPA with the help of phosgene. The material is crystal clear, lighter than glass, strong, and resistant to heat.
These properties led to hit application after hit application for the polycarbonate industry, including sheet to replace glass, housewares, car headlamp lenses, and optical media discs. According to the chemical consulting firm Chemical Market Associates Inc. (CMAI), global polycarbonate demand was 3.3 million metric tons in 2008.
In the current economy, the polymer has fallen on tough times. Overall demand in North America has dropped by 30 to 40% because of the recession, according to Roger Rumer, vice president of regional product managment for polycarbonate in North America at Bayer MaterialScience.
The industry’s problems cut deeper than the bad economy, however. The most notorious headache is BPA. Because BPA is a known endocrine disrupter, the industry is losing some food and beverage contact applications, particularly in products intended for children. A wholesale national ban of BPA in such applications hasn’t materialized, but voluntary substitution away from it by baby-bottle makers, retailers, and others is amounting to a partial ban.
Polycarbonate makers downplay the effect of BPA’s notoriety on their businesses. “We haven’t seen much of an impact on Bayer,” says Sam Stewart, vice president of sales and marketing for polycarbonate in North America at Bayer MaterialScience. “We still believe as a company, as most regulators do, that BPA is safe.”
The issue is less of a concern outside the U.S. and Canada, says Federico Montaner, Dow Chemical’s North American product director and global new business development leader of polycarbonate and compounds and blends. “There has been some conversion of baby bottles to alternative materials,” he acknowledges. “It is very much driven by consumer pull.”
Adrian Beale, director of global engineering resins at CMAI, differs. “BPA concerns for the food and beverage packaging sector are global, not just North American, although North America is leading the way,” he says. Products vulnerable to substitution of BPA represent about 5% of the global market, he adds.
Although polycarbonate makers are not admitting defeat over BPA, they readily acknowledge a problem in optical media applications. Consumers’ increasing reliance on the Internet for buying music has clobbered demand for compact discs.
The optical media market is the largest market for polycarbonate, representing 24% of demand, Beale says. Demand declined by more than 10% in the U.S. and 5% globally in 2008. “There is a correlation between the way the music industry moved away from vinyl records and the way it is now moving away from CDs,” he says.
The polycarbonate industry must develop new uses to make up for the ones it is losing, Montaner says. With its unique set of properties, polycarbonate offers a “very strong” value proposition, he says.
The industry is pinning much of its hopes on automotive glazing. Polycarbonate makers say the polymer has several advantages over glass in car windows: It is 40–50% lighter, which helps boost fuel economy, and it can be molded into shapes that are tough to accomplish with glass.
Polycarbonate is easily scratched and prone to weathering, however. The industry has been trying to overcome this major drawback for years. The two industry leaders, Bayer and GE Plastics, formed a joint venture, Exatec, to tackle these issues and found a way to deposit a protective plasma coating over polycarbonate parts.
In 2007, the joint-venture partners parted ways, and GE Plastics was purchased by SABIC. Instead of the plasma coating developed by Exatec, Bayer now uses a wet polysiloxane coating developed by Momentive Performance Materials. The technology is used on the 1.1-m2 roof panels of the Smart Fortwo car.
Automotive glazing can be a “game changer” for polycarbonate, Beale says. If polycarbonate were to substitute for all automotive glass except the front windshields, he says, the demand would represent about 40% of today’s market.
Makers of polycarbonate are targeting other emerging applications, including incorporation in photovoltaic panels and lenses for concentrated solar-power modules, and in lenses for electric bulbs based on light-emitting diodes. Medical applications, Bayer’s Stewart says, still have an annual growth rate of 5–7%.Overall
, growth will slow from the 8–9% rates of years past, and producers will have to settle for 4–6% growth after the recession, Bayer’s Rumer says. That is slower than during polycarbonate’s glory days, but it’s not bad for a product that has been around for nearly 60 years.
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