Green Scene: Using corn to make a polyester-like fiber

One outdoor industry company has just dipped its toe into the pond to test the market temperature of a new group of fabrics made from polylactide polymer (PLA), and it appears likely others will follow soon.
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One outdoor industry company has just dipped its toe into the pond to test the market temperature of a new group of fabrics made from polylactide polymer (PLA), and it appears likely others will follow soon.

PLA fiber is made from synthesized, polymerized plant sugar. Essentially, if you wanted to make PLA yourself, you'd take corn and mash it up to make dextrose. You'd let the dextrose ferment and that would produce lactic acid. A few more waves of the wand (hey, we've long since forgotten our organic chemistry from college) and you end up with PLA -- about one kilogram of PLA for every 2.5 kilograms of corn on average. After processing, PLA takes on properties that are very similar to virgin polyester. Currently, the only supplier with product in the marketplace is Cargill Dow with its Ingeo fiber which was introduced to the market in 2002.

Wickers is the first U.S. outdoor industry company to develop a product using Ingeo fiber, a women's base-layer top. Though the SNEWS® team has not tested it, we've touched it. Our initial read from package to desk is that the fiber has a very soft hand, and, at first glance, appears indistinguishable from polyester fibers made entirely from petroleum.

"The first thing that attracted us to Ingeo was the sustainability story," said Tony Mazzenga, CEO of Wickers. "We believe the environment is something that has to be of interest to everyone, and we think that Ingeo has a great story. It's a great fabric. The moisture transfer is amazing, and it's got a great hand. Even though we are using it in only a few items so far, it's been very successful."

Wickers first Ingeo T-shirt has only been available to consumers for two months; it is already expanding the line with additional styles and a wider range of colors. A men's long sleeve tee will be available in January.

Ingeo meets Wickers made-in-the-USA standards. Ingeo's polylactide manufacturing facility and lactic acid facility were constructed in Blair, Neb., near a corn wet mill (where the starchy component of corn is converted to dextrose used in the lactic acid fermentation process). All operations are within one industrial park in a state that is one of the United States' largest producers of cattle corn. This virtually eliminates transportation of raw materials, and means that Ingeo is 100-percent USA made.

What may be most exciting about Ingeo is its cradle to grave story. The fabric is made 100 percent from corn sugar that has been metabolized into PLA. Corn is, of course, an annually renewable resource. But the revolutionary part of the Ingeo process is that an Ingeo garment, packaging or other Ingeo product can be buried in an industrial compost pile at the end of its life, and it will turn to dirt in 60 to 90 days.

"Ingeo is limited only by the ways that the market wants to use it," said Joe Walkuski, former Patagonia fabrics guru who is now working with Cargill Dow to commercialize PLA in the United States. "It translates well into base layer, it doesn't absorb water, but attracts and wicks moisture naturally."

Traditional polyester needs to be chemically treated to get it to wick. Walkuski said that he thinks that some of the most interesting uses of Ingeo will be in blends with wool, Tencel, cotton, fleece or other fabrics. It's not just being used for apparel. PLA is also used for bedding, carpet, furnishings and personal care items, as well as in industrial applications.

Wickers reported no glitches in the spinning or knitting of Ingeo. Heat appears to be the primary limiting factor for Ingeo currently. It has a low melt point, so heat transfer and hot ironing are out of the question right now, although washing and drying do not require special handling.

While it appears that most agree creating a fabric that uses a renewable resource is a big step in the right direction, there are a number of industry experts who are quick to point out that Ingeo is and will be taking corn from the U.S.'s GMO (genetically modified organism) cattle feedstock, not organic or even non-GMO corn stock.

If a company wishes not to use GMO corn, Cargill Dow has an offset program. The manufacturer determines the amount of Ingeo it will buy, and Cargill Dow then works with one of its farmer-suppliers to grow the corresponding quantity of non-GMO corn. That corn will not be segregated, but will be added to Ingeo's raw material supply chain. Walkuski guessed the additional cost of the offset program for a manufacturer is probably under 5 percent, and definitely under 10 percent, but exact figures were not available.

Cargill Dow has completed lifecycle analysis of Ingeo, and though there are petroleum-based chemical pesticides and fertilizers used to grow the conventional corn used to make Ingeo, these petroleum inputs pale in comparison to the petroleum inputs needed to make conventional virgin polyester.

As for whether or not Cargill Dow will ever seek to manufacture PLA from organic corn, Walkuski said it is possible, though not likely that it will happen anytime soon. He said he firmly believes that with limited organic agriculture in the United States that organic corn should be used as people food not polymer. Because the molecular structure of the input sugar (in this case corn) is restructured to make PLA, there are no substantive differences between PLA made from organic, non-GMO or GMO inputs.

Rebecca Callahan Klein, executive director of the Organic Exchange, argued that because the very makeup of the input is molecularly changed, PLA would not qualify as an organic fiber anyway, so seeking to make the polymer from organic corn offers no real advantages.

"PLA fibers are made from taking raw materials and turning them into new materials," she explained. "The process reshapes a string of carbons. It's a polymerization process that fundamentally changes the input ingredients, and we think that it needs to be seriously considered whether or not the use of organic input materials would qualify this as an organic process." argi

SNEWS® View: As all good capitalists know, the greatest limits to how much organic corn is available is market demand. If Cargill Dow were to offer an organic corn-based PLA fiber to its customers, the backend could be developed to meet the demand. For a model, look at the organic cotton industry. Organic corn supply could be developed without affecting the supply of organic corn for food. Farmers are almost always willing to convert with a guaranteed buyer, and even more so if they get a slice of the proceeds pie. We hope that Cargill Dow will step up to the plate, expand its offset program, educate its customers about the advantages of organic and move toward organic instead of hiding behind excuses that don't offer much cover.

As far as the debate on whether PLA can be certified organic or not, we believe that the potential impact of making polyester from organic corn could significantly support organic agriculture. As of this writing, fibers are still being certified organic without regard to their final processing. And hey, cooking food in some cases changes its molecular structure. So, whether we label the fabric as made from organic corn or call the fabric organic is not the most important consideration right now. More important is getting to the point where those questions truly need to be considered.

For more information on PLA fabrics, visit www.ingeofabrics.com. Cargill Dow is debuting an online Ingeo fabric library accessible from the Ingeo website. For a somewhat one-sided viewpoint containing information on organic versus GMO agriculture, visit www.organicconsumers.org.

SNEWS® is very committed to further the communication of the green message. Our monthly "Green Scene" column takes a look at what our industry is doing well, what it can do better, and provide inspiration and ideas for establishing our industry position as the leaders in green for both preservation and profit. If you have ideas or issues you would like to see us discuss, send an email to: GreenScene@snewsnet.com.

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