“Even though only about 3% of oil goes into plastics, there is a lot of activity in biomaterials,” said Jay Olson, Manager, Materials Engineering, John Deere Moline Technology Innovation Center. (Some sources tack on an additional 4% to account for the energy expended in manufacturing polymers.) “Bio-based polymers are available and sustainable, and ready to hit a dramatic growth curve when they reach an economic point of substitution.”
Deere itself uses soy-based plastics for its HarvestForm composite exterior panels on tractors and combines. “We call it ‘from beans to machines,’” Olson said. “The panels are made from soy-based SMC [sheet molding compound], and we’re ready to implement soy-based polyurethane foams for seat cushions and interior padding as soon as testing is completed and sourcing issues are settled.”
In 1997, Deere-related research at the University of Delaware began on soy plastics, using seed funding from the United Soybean Board (USB). By 1999, soy-based polyester resins began to be commercialized by Ashland Inc. under the Envirez brand.
Using Envirez, in 2001, Continental Structural Plastics began making soy-based SMC that Ashley Industrial Molding Inc. was turning into a few small styling panels for a Deere combine. Finally, by 2002, soy-based SMC was going into all combine styling panels and, more recently, into tractor hoods and other agricultural equipment styling.
More recently, in 2007 Deere licensed soy-based foam technology for cushions fromFord Motor Co., whose research also was in part supported by the USB.
“The real push for using biomaterials came from our customers,” Olson explained. “And an appreciable amount of development funding came from customers directly, or indirectly through the United Soybean Board, whose farmer-members are our customers.”
The soy content is appreciable, but it is a minority member. The panels themselves consist of around 25% soy-based polyester resin—the rest is filler and fiber reinforcement, which in turn is around 25% bio-based, using both soybean and corn feedstock. The remainder of the polyester is petroleum-based.
That said, the soy usage adds up: the company projects allocation of 4 million lb (1.8 million kg) of soy-based SMC across its agricultural and off-road product line. And, each 38,000-lb (17,200-kg) batch of Envirez 1807 polyester resin saves 10 barrels of crude petroleum, a calculation that Ashland is quick to point out is based on net energy and oil usage consumed in manufacturing, as well as in farming and processing of soy into oil and corn into ethanol.
“We’re predicting 600 million lb usage across all possible uses for polyester compounds,” Olson said. This includes automotive, industrial, marine, computer/technology, and medical equipment products.
“The issue around adoption of soy materials is no longer around technical parameters,” Olson said. “Polyurethanes and polyesters, in particular, are equal in performance to oil-based resins. But first, there has to be demand, which is strong among our customer base. Partnership and cooperation all along the supply chain are a must. But the ultimate issue is economics—more biomaterials will move to widespread adoption once costs are equal as well. Deere’s attitude is to give preference to materials from renewable sources. If there is cost parity, why not do the right thing?”