Bizarre as that may sound, according to Ash Galbreath, director of Environmental Comfort & Engineering at Lear Corp. (Southfield, MI; www.lear.com), this undertaking, farm chemurgy, which involves using chemistry and other scientific processes to transform farm crops to industry products, is something that is being taken very seriously at Lear as they work toward more environmentally sound products and processes. A case in point is the company’s alternative to traditional polyurethane foam for seating. Although the company is deploying expanded polypropylene for some applications (e.g., the rear bench of the ’06 Chevy Impala and the rear bolster for the Ford Five Hundred), they’ve taken a page from Henry Ford’s book and are working with soybeans. That’s right, legumes, but rather than making body panels with soy beans, as Ford did back in 1940, they’re using soy oil in the formulation for polyurethane foam.
Galbreath explains they’re using the soy oil to create the polyol that’s mixed with isocyanate to create the foam. The polyol is not purely soy oil, but a blend consisting of petroleum-based polyol, soy polyol, catalysts, surfactant, and a blowing agent. Essentially, Galbreath explains, to produce the foam for applications including head restraints, arm rests, and seating surfaces—overall, there are 30 to 40 lb. of foam used in a vehicle interior—there is a mixture of 60% polyol and 40% isocyanate. Of the polyol blend, up to 50% soy oil content has been validated to have the required foam properties for auto manufacturers.
In addition to the fact that soy beans are a renewable resource unlike petroleum, there are other environmental advantages. There is a 100% reduction in CO2 emissions and 50% to 60% lower energy required in transforming the beans into oil as compared with processing petroleum. What’s more, there is the potential of reducing as much as 2/3 of the volatile organic compound emissions associated with creating the foam (apparently, there are no free amines after foaming as there are when conventional petroleum-based foams are produced).
Lear is working with several partners in the development of what it has named its “EnviroTec” material. They include: Ford Motor; Renosol Corp.; Bayer Corp.; Dow Chemical; Urethane Soy Systems Co.; and United Soybean Board-New Uses Committee.