June 26, 2006 | General

Plastics From Plants, Not Petroleum

BioCycle June 2006, Vol. 47, No. 6, p. 33
This concluding report examines such issues as recyclability, life cycle analyses, retailer acceptance and industry outlook. Part II
Diane Greer

Determining the “greenness” or sustainability of bioplastics is based on a variety of factors including raw material sources, nonrenewable energy utilization, manufacturing techniques and end of life disposal options. One end of life “disposal” option is composting. A sidebar in Part I of this article, (May 2006) discussed specifications for biodegradability in a composting environment. Specifications were developed by the American Society for Testing and Materials; ASTM D6400 and ASTM D6868 require materials to disintegrate and biodegrade under commercial composting conditions and the resulting compost to be able to support plant life.
An industry group, the Biodegradable Products Institute (BPI), verifies the manufacturer passed the ASTM tests in an approved lab, explains Steve Mojo, Executive Director. BPI also looks at company information and employs independent reviewers to examine formulation information. Almost two dozen resins and products, including bags, films and food serviceware, have been certified. The next frontier for the biodegradable products industry is having a composting infrastructure across the country that can receive and process the biodegradable, compostable plastics. (See “Biodegradable Plastics Make Market Inroads,” May 2006 for a discussion of this issue.)
While solutions are being worked out on the composting side, one of the disposal hurdles facing bioplastics manufacturers is the recyclabilty of its products. The presence of certain bioplastics in the recycled plastic stream is actually causing problems. For example, PET, which has the highest recycling rate in the U.S., is very sensitive to contaminants. Small amounts of PLA in the PET recycling stream can result in recycled PET bottles with black spots, explains Dr. Donald Rosato, Senior Research Analyst with Frost & Sullivan.
Markets for postconsumer PLA (polylactic acid) will develop as the volume of bioplastics increases, providing an outlet for reclaimers of recycled products to sell recovered PLA materials, according to Glenn Johnston, Manager of Global Regulatory Affairs for NatureWorks LLC, a subsidiary of Cargill that manufactures PLA. He foresees a day when recycled PLA could be hydrolyzed back into lactic acid and remade into new products, similar to recycled aluminum and glass.
In the interim, NatureWorks introduced a Bottle Recycling Buy Back Program. Under the program, NatureWorks will buy, at an agreed-upon price, truckload quantities (40,000 lbs.) of PLA and send the material to an appropriate end-of-life solution. David Luttenberger, Director of Packaging Strategies, feels the program is admirable but premature. “They announced that tens of thousands of tons was their goal,” says Luttenberger. “But how are they going to collect all this? How are recycling centers going to identify this stuff?”
Identification is a problem for recycling centers sorting materials by hand. In those cases, it is next to impossible to differentiate a PET bottle from a PLA bottle. It is possible to sort PLA from other recycled materials using current infrared technologies, according to Johnston.
One of the most effective means to determine the sustainability of a product is through life cycle analyses (LCA). LCA looks at the environmental and economic impact of every stage of a product, from raw material extraction to manufacturing to product disposal. Several of the bioplastic manufacturers have commissioned or conducted LCA studies. The results indicate significant strides in reducing the environmental impact of bioplastics when compared to petrochemical-based plastics.
“NatureWorks conducted peer-reviewed research to evaluate all the inputs and outputs of the PLA production system from the cradle (corn production) to the NatureWorks PLA factory gate,” says Johnston. The LCA found NatureWorks PLA uses 30 to 40 percent less fossil fuel resources and emits 20 to 50 percent less greenhouse gases than traditional petrochemical plastics. The company also has purchased Renewable Energy Certificates (RECs) to offset its fossil fuel use and the resulting greenhouse gas emissions, according to Johnston.
Earthshell, which manufactures bio-degradable products using a biopolymer made from potato and corn starch, limestone and water, commissioned Franklin Associates to conduct an LCA, according to Vince Truant, Chairman and CEO of EarthShell Corp. The study found Earthshell plates and bowls used 64 to 75 percent less energy than equivalent products produced from polystyrene, and 39 to 50 percent less energy than products made from paper. Greenhouse gas emissions were 49 to 59 percent less than polystyrene products and 27 to 45 percent less than paper.
First generation technology from Meta-bolix – which developed a fermentation process to produce polyhydroxyalkanaotes (PHA) polymers (see Part I for details) – shows 20 to 50 percent less fossil carbon energy content than conventional plastics along with lower greenhouse gas emissions, according to Jim Barber, President and CEO of Metabolix. The production of PHA in switch grass holds the promise of creating a renewable energy source in conjunction with the production of plastic.
Retailer acceptance is a key hurdle for the green plastics industry. “There has to be a considerable economic advantage, a consumer driven demand and there has to be acceptance by retailers,” says Luttenberger. He points out that brand owners need to ensure the new packaging is going to “make it” through their distribution systems and prove satisfactory to customers. “With very few exceptions, brand owners are not going to change just for the sake of changing,” he adds.
Joe Selzer, Vice-President of Marketing and Sales for Wilkinson Industries, a producer of PLA food containers, sees a reluctance by some retailers to change. “Even though it is price competitive and environmentally friendly, people are still kind of afraid of it at this point,” says Selzer. “I think the Wal-Mart announcement (see below) has helped tremendously.”
Bioplastics also are disadvantaged since converting manufacturing operations to use bioplastics still involves costs. “There is the tool barrier to entry when you are making smaller volume runs and then there is a basic incompatibility in the processes,” adds Rosato. “You may have to modify equipment or in some cases buy new equipment.” Notes Selzer in speaking about manufacturing products from PLA: “You do have to make some modification to the equipment, both from an extrusion and thermoforming perspective.”
This situation may change as new bioplastics come on the market. For example, Metabolix claims its resins will be able to run on conventional equipment, according to Barber.
Finally, while some bioplastics are competitively priced with their petrochemical cousins, others are still more expensive. “Currently from an overall price comparison standpoint, bioplastics are 2.5 to 7.5 times more expensive than traditional major petroleum based plastics,” says Rosato. “With the potential of volume, this could go down to a 1-to-3 times range. But we are still probably three to five years away from a break point.”
Despite the challenges, there are plenty of positive developments. More and more corporations are seeing the benefits of corporate sustainability initiatives. “This is more than an environmental fad du jour,” says Luttenberger. “The whole area of bioplastics and renewable materials, within the context of corporate sustainability initiatives, has begun to ring true in the boardrooms.”
The emphasis on sustainability is starting to pay off for bioplastic manufacturers as some large brands start switching to packaging made from bioplastics to show their commitment to corporate sustainability. In WalMart’s recent announcement about replacing an estimated 114 million PET containers with NatureWorks PLA containers, the company highlighted the estimated savings of 800,000 gallons of gasoline and the reduction of 11 million pounds of greenhouse gas emissions resulting from the conversion.
The presence of larger industry players entering the market is helping with product acceptance and providing an air of legitimacy. Companies like Archer Daniels Midland and Wal-Mart either investing or making volume commitments will help to speed the commercialization of the bioplastics industry.
The demand for bioplastics is also being fueled by legislative initiatives. In Europe, Extended Producer Responsibility (EPR) laws are requiring manufacturers to take responsibility and assume the cost for the waste generated from the products they produce. Incorporating the cost of waste disposal in their product is leveling the economic playing field for biodegradable and compostable packaging made from bioplastics.
Other factors driving demand include government green buying programs and corporate sustainable purchasing initiatives. In the U.S., the Farm Security and Rural Investment Act of 2002 confers federal purchasing preference to biobased products.
Most forecasts for the bioplastics industry see robust growth. Frost & Sullivan is projecting worldwide plastic consumption to increase from 180 million tons to 258 million tons by 2010. “Of that, between 1.5 to 4.8 percent will be bioplastics,” says Rosato. He believes that North America will account for about 15 percent of the bioplastic market.
By 2020, Toyota officials expect one-fifth of the world’s plastic will be bioplastic, equivalent to 75 million tons. Over the next five years, BASF expects the world market for biodegradable plastics to grow by 20 percent per year. BASF manufactures EcoFlex, a biodegradable polymer, and recently introduced Ecovio, a blended polymer made with 45 percent PLA and 55 percent EcoFlex.
Current bioplastic resin manufacturers are seeing strong sales growth. Sales volume of NatureWorks PLA and its Ingeo Fibers registered 230 percent from 2004 to 2005 and is projected to be in the triple digits for 2006, according to Johnston.
While not completely sustainable, the production and use of bioplastics go a long way toward solving the environmental problems posed by petrochemical-based plastics. Ultimately, bioplastics’ success will be driven by its performance and cost competitiveness versus traditional plastics. Rosato also emphasizes the commercial and technical feasibility of production and processing options as another key determining factor. Government initiatives and regulations also will play a role, spurring demand and providing economic incentives.
Diane Greer is a free-lance writer and researcher based in New York, specializing in sustainable business, green building and alternative energy. She can be reached at

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