Ford finds alternatives to petroleum parts
by Irwin Rapoport

With the Ford Motor Company using wheat straw biofiller to replace 20 percent of the petroleum-based plastic used in just two internal storage bins for its Flex crossover vehicle, the automobile manufacturer is simultaneously creating a demand for an agricultural waste product and reducing the carbon footprint of its manufacturing process.

The new bins, currently being installed in the 2010 Flex, replace bins that were made from 100 percent petroleum-based plastic. For the Flex bins alone, using environmentally-friendly wheat straw will reduce petroleum consumption by 20,000 pounds annually and reduce CO2 emissions by 30,000 pounds per year.

“This first application is relatively small,” said Dr. Ellen Lee, a chemical engineer and technical specialist with the Plastics Research Group at Ford’s Research and Innovation Center in Dearborn, Michigan, “but it represents a smart, sustainable usage for wheat straw; the waste byproduct of growing wheat. There are a lot of other potential applications that it can be used for. We are putting wheat straw fiber in with polypropylene to give the plastic more strength and stiffness properties.

“The new material is also lighter in weight and less costly than similar grades of glass fiber or mineral reinforced materials that we use today,” she added.

Ford researchers were first approached with the wheat straw-based plastics formulation by the University of Waterloo in Ontario, Canada as part of the Ontario BioCar Initiative – a multi-university effort between the Universities at Waterloo, Guelph, Toronto and Windsor. The universities receive funding from Ontario’s provincial government, which wants to promote the use of more plant-based materials in the automotive industries. The wheat straw-reinforced resin is the BioCar Initiative’s first production-ready application. It also demonstrates better dimensional integrity than a non-reinforced plastic and weighs up to 10 percent less than a plastic reinforced with talc or glass.

The success in developing the new material was based on a collaboration that brought together private industry, government and university research departments.

The wheat straw injected plastic is manufactured by Akron, Ohio-based A. Schulman, a plastics supplier, who was working the University of Waterloo to develop injection molding compounds that contain renewable materials that not only meet auto industry standards for thermal expansion and degradation, rigidity, moisture absorption and fogging, but are also odorless.

Dr. Debbie Mielewski, a chemical engineer and leader of the Plastics Research Group at Ford, said the cooperation between all of the different stakeholders was essential for success in developing an approved sustainable material in less than 18 months.

“The University of Waterloo did a lot of the up front fundamental research, and A. Schulman did the formulation and scale up of processing. The Ford team was involved in the collaboration early enough to advise the team on appropriate targets and applications,” she said. “Together, we’ve developed a material that we think we can migrate to other platforms and applications – then, the environmental benefits really begin to add up.”

The Flex crossover is built at Ford’s Oakville (Ontario) Assembly Complex.

Research, thus far, has found the 20 percent replacement level is the perfect mix.

“We would not want to go higher because as you increase the filler loading,” said Lee, “the impact properties start to degrade. We see a great deal of potential for other applications since wheat straw has good mechanical properties, can meet our performance and durability specifications, and can further reduce our carbon footprint – all without compromise to the customer.”

In terms of other products that can be made with wheat straw filler, Ford is looking at center console bins and trays, interior air register and door trim panel components, and armrest liners.

“There are also a lot of applications under the body,” said Lee. “Many underbody shields are large enough that if replaced with wheat straw composite, would offer significant weight savings.”

In terms of recycling the bins, tests conducted by Ford have found that the bins cans be recycled similarly to other plastic composite materials.

Mielewski is eager to see wheat straw used to reinforce plastics in higher-volume, higher-content applications in products across the board. Wheat straw can be supplied on a long-term basis. In Ontario alone, at least 28,000 farmers grow wheat, as well as soybeans and corn. Should the wheat straw and other agricultural waste byproducts, which could be used to reduce petroleum-based plastics, be harvested from the corn and wheat belts in the United States and Canada, where millions of acres are farmed, the material could play a major role in reducing oil consumption.

“Wheat is grown everywhere and the straw is in excess,” said Lee. “More importantly, it doesn’t jeopardize an essential food source.”

Studies in Ontario have found that there is 30 million metric tons of available wheat straw waste at any given time. Thus far, 4 southern Ontario farmers are supplying wheat straw to Ford and its suppliers.

Ford also began using soy-based foam in the Mustang’s seats since 2007. The automaker has migrated the product to additional vehicle lines, now manufacturing more than 1 million vehicles a year with soy seat cushions and backs.

Ford calculates that they are currently using about 1 million pounds of soy oil and reducing CO2 emissions by 5.3 million pounds annually. Moreover, the company is looking at using soy fillers in plastics and rubber to further reduce the carbon footprint of its vehicles.

The alternative foam, developed at the Ford Research and Innovation Center is now being used in its F150, Navigator, Escape, Expedition, Focus, Mercury Mariner and Lincoln MKS.

“This year, we added soy-based foam to the headliner in the Escape,” said Dr. Cynthia Flanigan, a materials scientist with Ford’s Plastics Research Group. “We are expanding the applications beyond seating and are starting to make a significant impact, not only at Ford, but throughout the whole industry as other OEMs start to pick up the soy foam technology.”

The percentage of soy foam used in the seats is currently around 12 percent, “But we can formulate headrests, armrests and other parts that can go up to 40 percent soy content,” said Mielewski.

To create the soy foam, producers use the oil from soybeans which is heated while exposed to the air and oxygen, which hydroxylates it to create a soy-based polyol. The soy polyol is mixed with petroleum-based polyols and several other components to form the polyurethane foam.

Soy oil is used by the fast food industry to cook items such as french fries, as well as being a standard cooking oil. The United Soybean Board (USB) approached Ford with the concept of using soybeans as a feedstock for alternative automotive materials.

“The soy oil molecule is flexible chemistry-wise and the soy polyol is similar in structure to that produced from petroleum,” said Mielewski. “The United States has an excess of soybeans and the USB’s New Uses Committee is always looking for new applications for soy. The committee awarded us with grants to scale up our research from the laboratory to production equipment and prove it out so that industry could see that it was possible.”

Initial efforts in 2001 at making soy foam were not impressive, and creating a successful formula took years.

“Everybody was saying ‘you can make a soy foam easily,’” said Mielewski. “We gave it a try and we got absolutely miserable foams that nobody would use for anything. It took us another 3 years, but we eventually did it. We showed our first foam that met Ford specifications in 2005, and we launched in 2007. It’s a long-term commitment to develop these brand new, sustainable materials from research to production.”

According to Lee, “What we are saving today by using these biomaterials is equivalent to over 58,000 tree seedlings in the ground growing for 10 years. Every little bit helps, like reducing weight with the wheat straw reinforced plastics.

“In the longer-term, we are looking at completely compostable resins – PLA – made from corn, sugar beets or sugarcane and even switchgrass,” she added. “Our challenge for these materials is to improve the durability for automotive use, yet maintain its compostability at the end of life.”

“Other biomaterials we are currently developing are making use of the other half of the soybean, the protein half, as a soy meal or soy flour, in various plastics and rubber materials,” said Flanigan.

Ford has three United States patents pending on soy foam, including formulation, synthesis and odor reduction.

Eliminating the odor was a major technical challenge that had to be tackled; otherwise it would not have been considered a viable replacement to oil.

Lee notes that the desire to replace petroleum-based car parts with sustainable materials is based on the high price of oil and improved technologies and equipment to carry out research.

“The customer has to want it as well,” she said. “We don’t put things on vehicles that have no interest. The price of oil spiked, people became more interested in conserving the environment and our materials were in the final stages of development, which was kind of lucky.”

“It’s not just about meeting current specifications for petroleum-based products, but surpassing them,” Mielewski added. “We have found that some of the biomaterials we have been developing show improved function or qualities that do not occur with the petroleum-based materials.”

Ford’s soy foam innovations have been recognized, with the company receiving the Society of Plastics Engineers Environmental Award (2007), the Global Plastics Environmental Conference Environmental Stewardship Award (2008) and within Ford, the 2008 Henry Ford Technology Award.