Plant oils used for novel bio-based plastics

Researchers have developed a new way to use plant oils like olive and linseed oil to create polyurethane, a plastic material used in everything from foam insulation panels to tires, hoses and sealants. 

Polyurethane is extremely tough and corrosion- and wear-resistant, but researchers would like a more environmentally friendly alternative to the petroleum-based product. About 14 million tons of polyurethane was produced in 2010, and production is expected to increase by almost 30 percent by 2016.

While there are already some polyurethanes made from plant materials, Kessler's research group developed a new method that uses vegetable oils to create materials with a wide variety of flexibility, stiffness and shapes. Plant oils are inexpensive, readily available, renewable and can be genetically engineered.

In the study, the researchers made polyurethane using olive, canola, grape seed, linseed and castor oils. While other researchers have struggled with using petroleum-based solvents, the WSU researchers, working with colleagues from Iowa State and from Cairo universities, didn't use solvents or a catalyst in their production.

"The novelty of this particular work is that these polyurethanes are using a new chemistry made by a combination of castor oil fatty acid and modified vegetable oils," Kessler said.

Kessler, who is director of the Center for Bioplastics and Biocomposites, hopes that the method is appealing to the plastics industry. The center, a collaboration between WSU and Iowa State University, is the first industry and university cooperative research center devoted to the development of biologically based plastics.