Theres some encouraging news for polylactic acid, the promising but beleaguered corn-based polymer intended to replace conventional petroleum-based plastics and help usher in a new era of biobased products.
Corn-based plastics have been around since the 1930s, when Wallace Carothers, a scientist for Dupont, produced a low molecular weight product by heating lactic acid under a vacuum. But they became the darlings of what some have come to call the carbohydrate economy in the 1980s when Cargill, one of worlds largest food companies, began to develop polylactic acid polymers. In 1997, Cargill formed a joint venture with Dow Chemical Co. to Cargill Dow Polymers. Together they built a large-scale $300 million PLA manufacturing facility in Blair, Nebraska, about 20 miles north of Omaha.
But sales of PLA plastics have been slow to take off. In June, Dow announced it was pulling out of the joint venture, cutting its losses at about $750 million. Cargill rechristened the company as NatureWorks, reflecting the brand name of its flagship PLA product. Sales are growing, but the plant is operating well below capacity.
The problems have been largely economic. In a world in which plastic remains largely a commodity, NatureWorks is a more costly alternative for its principal uses: for packaging material, from plastic bottles to film wrap, and for fibers used in pillows, comforters, and apparel.
Another challenge for PLA are genetically modified organisms, or GMOs. Because about 30% of the U.S. corn supply is genetically modified, some potential PLA customers -- progressive food and apparel companies, for example -- have been reluctant to have their PLA-based products tarred by the Frankenfoods brush. (It should be noted that no GMO corn molecules actually end up in PLA material; it dies off during the fermentation process. But many activists believe that supporting PLA means supporting conventional corn production.)
Still another challenge is that part of PLAs promise -- its biodegradability -- has been stymied by the relative lack of composting programs in the United States.
Things have looked bleak. Environmentalists and entrepreneurs agree that if Cargill cant make a go of bioplastics with all of its hundreds of millions invested, probably no one can, either. And if NatureWorks goes belly-up, it will be a long time before investors pony up for another bioplastics plant.
But two recent developments are encouraging. Earlier this month, DuPont and Tate & Lyle announced that they plan to open a new $100 million plant in Tennessee that uses biobased resources to make high-performance products. Scientists from the two companies have developed a new method to use corn to produce 1,3 propanediol (PDO). The resulting product, Bio-PDO, is a key ingredient in the production of DuPont Sorona, a DuPont polymer used for clothing, carpeting, plastics, and other products.
Producing Bio-PDO consumes 30-40% less energy per pound than petroleum-based PDO. Production of 100 million pounds of Bio-PDO will save the equivalent of 10 million gallons of gasoline per year, say the companies. The U.S Environmental Protection Agency presented DuPont with its annual Presidential Green Chemistry Award in 2003 for the company's research leading to the development of the Bio-PDO process.
Meanwhile, NatureWorks recently announced plans to launch a large-volume buy-back program in North America for post-consumer bottles made from PLA.
Through the buy-back program, commercial municipal recycling facilities in select geographic areas will separate post-consumer PLA bottles into bales, which NatureWorks will buy. The company will take them to an appropriate end-of-life solution and/or post-consumer use based on geography of collection and prevailing market economics, it says. PLA can be sorted from other plastics using standard near-infrared equipment.
NatureWorks says it hopes the program will help create a bridge to the development of a commercially viable post-consumer PLA market -- and that can only result in increased market acceptance for PLA itself.
Joel - it's great to have you on as a contributor!
It's good to hear that NatureWorks is considering a takeback scheme for dealing with the waste diversion issue; most of the time that I've seen biopolymer food packaging used, it's ended up right back in the trash/landfill, missing the point entirely. So this begins to put a missing part of the system in place.
My real concern remains the net use of petrochemicals, and the impact of industrial ag: how much oil are we using in the life cycle (on agriculture inputs, energy, transportation for distribution and - now - takeback) to save on the landfill that might have been created with traditional plastics?
Besides the GMO-corn argument, I've been under the impression that the main issue with biopolymers was the net use of petroleum products. So I'm left with more of a question than a critique: is anyone working to develop a technology or process that resolves this imbalance in the life cycle? I recognize that the business case issue (with the new Bio-PDO plant, for instance) is key. I just get worried when we see materials like this as a magic bullet, especially when their net impact can arguably be worse than before. This is a real issue as product designers get more interested in sustainability.
(The Industrial Ecology of Biobased Products is another free-for-download issue of the Journal of Industrial Ecology (Joel blogged about a more recent one in June) that covers some of these issues in super-academic detail. Just some further related reading, not all of which I've done...)
i was watching an video clip from a speech that janine benyus made at bioneers and she mentioned a researcher at cornell who is working on making a plastic from organic peels and excess carbon thereby using a waste product and helping to sequester c02. it doesn't completely address the concerns you mentioned in regards to fossil fuel use in production etc...but it does seem like a more enviromentally proactive (and non-gmo) alternative to corn plastics.
did some research and found this:
Date: Sat, 29 Jan 2005 09:22:59 -0500
To: ETList, LuMag List, o2 List
Subject: [o2mailinglist] Orange Peel Polymer :: ergo Citra-Solv Plastics!
Oranges Are Good For You (And The Earth)
01.20.05 by Dominic Muren
Two of the top stories of the last year have been that world oil production is peaking, and that climate change is real, and human-caused. And interestingly, this week, Cornell University researchers announced a new type of plastic which is a first step toward addressing both problems. Thank your lucky stars for oranges.
Cornell Scientists announced this week that they had developed a novel polymer composed of an oily component of orange peels, and carbon dioxide. Since CO2 is a greenhouse gas currently being held responsible for a large amount of climate change, sequestering it in non-atmospheric form is a pressing concern. Hundreds of different ideas, from pumping liquid CO2 to the bottom of the ocean, to injecting it into abandoned wells have been proposed, but most are too expensive, or ineffective.
However, if this process could store a viable amount of CO2, the process could actually be made to make money, since at the end, you would have saleable plastic. Furthermore, since this plastic requires no petroleum products (Other than to power the equipment to make it, but this could utilize a non-petroleum power source), it would ease our need for oil.
This is just the latest and most thorough success in a growing movement to utilize industrial waste streams as resources. Products like Ultratouch insulation, which uses offcuts of cotton cloth for fiber, or Smile Plastics
which re-forms reject plastic parts into unique raw plastic sheeting, are also helping to turn the tide of material use and waste production. Or, on the pure product end, MIO culture lab converts the waste stream or derelict manufacturer directly into new products.
So what about your product? Is there some wastestream just waiting for you to claim it?