Harvest Season Ahead For Soy Resins

Five hundred thousand pounds. That is the commitment that motorized equipment manufacturer John Deere (Moline, Ill., U.S.A.) has made thus far to using soy-based resins in its line of farm equipment. Its soy- and corn-resin-based HarvestForm panels appear on some of its larger combines and tractors. Due to the cost savings and performance advantages, the usage of this soy-based technology is only expected to increase.

Despite popular beliefs, use of soy-based resins is nothing new. In 1933, Henry Ford replaced a small portion of the rear of one of his automobiles with soy-based phenolic plastic. To display the strength of the material, he took a sledgehammer to the rear panel. The soy-based plastic demonstrated excellent strength and flexibility. It reacted much the same as any reinforced plastic would. However, petroleum-based resins were in greater supply and more inexpensive after World War II. Therefore, relatively little new research on using soybean oil and protein as industrial ingredients was conducted until formation in 1991 of the United Soybean Board (USB, www.unitedsoybean.org/newuses). USB, made up of 64 volunteer farmer-directors, oversees investments of the soybean checkoff, a research and promotion program funded by U.S. soybean farmers. USB efforts have funded research and development of soy-based resins and have moved them from a fringe ingredient to a recognizable part of the plastics and foam production industry.

An example of this farmer commitment to advancing soy-based plastics is that of South Dakota Soybean Processors, a farmer cooperative, and its work with Urethane Soy Systems Co. (USSC). With help from USB and the soybean checkoff, USSC was able to achieve great success in the marketing of soy-based polyol technology in less than five years.

A soy-based polyol combined with isocyanate creates a polyurethane resin system. This ingredient can be used in both rigid and flexible polyurethane foam applications for everything from construction materials like spray-foam insulation to household uses.

SoyOyl, the patented soy polyol developed by USSC, is currently being used in the manufacturing of several polyurethane plastics. Until the development of SoyOyl, polyols had been made almost entirely from petroleum-derived chemicals. The soy polyol also requires much less energy to produce. This makes it more affordable, as those savings are passed on to end-users. The performance advantages and savings make SoyOyl a lucrative product for a large number of rigid and flexible foam and coating applications, ranging from the exterior combine panels to truck-bed liners, seat cushions and even carpet backing and footwear.

Further, a recent life-cycle analysis of soy polyols revealed that they have roughly one-quarter of the environmental impact of petroleum-based polyols. The examination, conducted by the National Institute of Standards and Technology using the Building for Environmental and Economic Sustainability (BEES) model, analyzed the entire cycle of the life of a soybean from growing them to using the soybean oil in polyurethane and polyester applications. The BEES analysis suggests that the usage of soy as a raw material could result in significant reductions in global warming, smog formation, ecological toxicity and fossil fuel depletion. Soy polyols help to lower global warming by reducing carbon dioxide in the atmosphere. For every 1 lb of soybean oil used, almost 3 lb of carbon dioxide is taken out of the air.

These are attractive results for manufacturers faced with increasing government restrictions on pollution and volatile organic compound (VOC) emissions. Government agencies also are drawn to using soy-based polyols due to the most recent U.S. farm bill, which contains a bioproducts initiative. The initiative is meant to encourage federal agencies to purchase biobased products if their cost is not unreasonably higher, they are readily available and they meet performance requirements.

Many major manufacturers have taken notice of the benefits of using soybean oil-based resin technology. John Deere is using HarvestForm Reaction Injection Molding (RIM) on the rear panel of its combines, incorporating Baydur polyurethane resin compound, developed by Bayer MaterialScience LLC (Pittsburgh, Pa., U.S.A.). Ten additional exterior panels are molded by Ashley Industrial Molding Co. (Ashley, Ind., U.S.A.) using HarvestForm Sheet Molding Compound (SMC), compounded by ThyssenKrupp Budd (Troy, Mich., U.S.A.) from chopped glass impregnated with Envirez 5000 soy-based thermoset polyester resin from Ashland Chemical Co. n Composite Polymers Div. (Columbus, Ohio, U.S.A.). About 370 lb of the SMC are used for each John Deere combine that leaves the assembly line. Farm equipment manufacturer, Case New Holland (CNH, E. Moline, Ill., U.S.A.) also uses this same SMC. CNH uses a soy polyurethane material for exterior trim on its combines and tractors and manufactures a tractor cab roof using a soy polyester material.

Both companies say the soy resin panels are stronger, easier to paint, more flexible, lower in repair costs and lighter in weight than steel parts that were previously used in equipment. Soy resin panels also display significant corrosion resistance over time. Due to the cost and energy savings, John Deere is looking to increase its usage of soy-based polyols and incorporate the same technology into the seat cushions of its tractors and smaller equipment.

Agricultural manufacturers are not alone in taking note of these performance advantages. Ford Motor Co.'s long-standing interest in soy-based products continued in 2003, with the introduction of its Model U, a "Model for Change" for the 21st Century. Manufactured using processes and materials that are safe, productive and restorative, it runs on clean, renewable energy. Among the most impressive features is its soy-composite tailgate.

Soy-based sprayable, open-cell, moisture-, mold- and mildew-resistant semi-rigid foams, which expand to 100 times original liquid size, are now used as home insulation. It behaves much like a petroleum-based plastic foam, without the environmental side effects.

The farmer-leaders of the soybean checkoff see the success of soy polyols thus far as the tip of the iceberg. Soy polyol flexibility of use and potential in the marketplace are the primary reasons why the soybean checkoff continues to fund research on soy polyols and soy plastics.

Although the North American market represents only a third of the global market for polyurethanes, its demand for polyols has reached 3 billion lb, of which 800 million lb can be made with the more cost-effective soybean oil. With major manufacturers like John Deere and Ford Motor Co. constantly looking for ways to expand their biobased applications, the market potential for soy resins and polyols in the United States is one that is far from being realized.