Plastic goods for your compost heap

At a press conference here Monday, Metabolix announced the brand name--Mirel--for its biodegradable plastic made from corn and said it will be used in several consumer products including razor holders and gift cards.

The plastic pellets will be produced through a joint venture called Telles between Cambridge, Mass.-based Metabolix and ADM, which expects to have a corn-processing plant in Clinton, Iowa, operating in the second half of 2008.

The idea behind Mirel is to brand products or their packaging as a greener alternative to conventional plastics, which are made from petroleum, said Metabolix CEO James Barber. Like a growing number of "green," or so-called clean tech, companies, Metabolix is appealing to consumers' growing concerns over the environment and sustainability.

Companies can use the Mirel logo to indicate that it's an Earth-friendly plastic that can decompose within a few months, depending on the circumstance.

By contrast, things like plastic bags--part of the 350 million pounds of plastic created every year--remain in the environment "virtually forever," Barber said. The petroleum to make these plastics accounts for 10 percent of the oil the U.S. consumes, he said.

Metabolix expects that consumer-goods packagers will charge slightly more because they are "premium" goods. A coffee sold in Mirel packaging, for example, would cost consumers a few cents more, Barber said.

Metabolix is in talks with 40 prospective customers for 60 different applications including coffee cups and lids and plastic bags, he said.

Plastic microbes
American Excelsior has already developed a line of plastic stakes to hold down its erosion prevention blankets. The plastic stakes are better than metal stakes because they will not rust in seawater and don't require crews to retrieve them at the end of their use, said Jerry Bohannon, director of earth science at American Excelsior.

The company will also upgrade its software so that engineers can design systems around biodegradable products, a move that will allow "engineers to create products with the environment in mind," Bohannon said.

Mirel will initially be made from corn starch, but other sources of sugar can be used as well.

Meanwhile, Metabolix is already at work on a second generation of plastics grown within plants.

The company is developing a method by which the microbes that make up its biodegradeable plastic can be produced within switchgrass, Barber said.

The microbes, which are innocuous to the switchgrass they're growing in, can be extracted and made into plastic pellets. Residual biomass also could be converted into biofuels. "It'll be huge," he said, adding that the process will be available in about five years.

Mirel plastic stems from genetic research started at the Massachusetts Institute of Technology nearly 20 years ago.

The plastic is made by combining genes of several naturally occurring substances and making them function together, said Oliver Peoples, chief scientific officer and co-founder of Metabolix.

Genetic engineering is well understood but hasn't been widely applied to plastics, he said. Mirel uses many of the same techniques that pharmaceutical companies do.

"We are interested in using a number of genes to assemble teams of genes and make them work in living cells," Peoples said.

Metabolix executives said PLA does not stand up as well to heat as Mirel and can be composted only in industrial composting facilities.

Mirel plastic can biodegrade in soil or any type of compost pile. It will also break down in septic systems and waste treatment facilities or in wetlands and marine environments.

"The key thing with Mirel is that it opens up a range of options for the end-of-life fate," Barber said. "Now plastics last hundreds or thousands of years."

On the other hand, PLA is clearer than Mirel, so most likely it will be used to package products that will be chilled, like produce or sandwiches, Barber said.

Another company called Cereplast is also making biodegradeable goods, such as food packaging and utensils, from corn starch.

In contrast to Metablox, Cereplast said that with rising petroleum prices, its corn-based products will be the same price or cheaper than traditional plastics.

ADM chose to partner with Metabolix because its patented technology makes it a leader in the field, said Terry Stoa, vice president of technology assessment at ADM.

He said that the production plant, now under construction, will be capable of making 110 million pounds of Mirel per year.

Although the company is betting that consumers will be willing to pay more for Mirel as a green product, company executives concede there isn't a great awareness of how plastics are produced today.

A study commissioned by Telles found that 72 percent of the American public does not know that conventional plastic is made from petroleum.