Converting crops into cars

Pioneering auto maker Henry Ford was a man before his time. In the 1940s, his vision to "grow automobiles from the soil" resulted in an experimental car made of resin-stiffened hemp fibre, more resistant to denting than steel.

More than half a century later, an industry partnership between the Ford Motor Company and the University of Toronto's Dr. Mohini Sain and his collaborators are resurrecting Ford's dream. The chemical engineer is developing technology that will replace the sheet metal and glass fibre used to build cars with natural fibre composite materials, such as hemp.

Industrial hemp is a tough, fibrous plant, with thousands of potential uses, from the manufacture of textiles and rope, to paper, construction materials and plastics. "Hemp is an exciting fibre because it has a springy characteristic," Dr. Sain explains. "It's capable of energy absorption, so it's very suitable for automotive or aerospace applications where you are looking for safety and crash-resistance properties."

A pioneer in the field of nanobiocomposites, the NSERC-funded scientist is making new biomaterials by incorporating nano-sized biofibres from plants such as hemp, straw, wheat, corn and even turnips, into bioplastic materials made from soya beans or pulp and paper sludge.

Biofibres are extracted from plant stalks by first separating the pectins and cellulose, and then blasting the remaining plant material under high pressure until it is reduced to a powder as fine as corn starch. Dr. Sain has applied for a patent for his state-of-the-art process that extracts nanofibres from plants.

He is also using the same process to turn waste wood from demolished buildings into biofibres that can then be used to make high-performance materials.

When the nanofibres are combined with bioplastics, the resulting high-performance composites can be used to make not only interior and exterior car parts, but airplane wings, railway crossties, building beams and biomedical devices such as cardiac valves and intravenous blood bags.

Biocomposite materials made with hemp have been commercialized for use in decks, fences, shingles, siding, docks, and patio furniture. "We are also expecting it to penetrate the sports market, for making helmets, skateboards and canoes," says Dr. Sain.

Dr. Sain will be the director of the proposed Centre for Biocomposites at the University of Toronto, which aims to educate people and improve awareness of biomaterials and their applications. "The centre will be the heart of the biocomposite and biomaterials research in Canada," he says. "We will collaborate with eight universities from coast to coast, with more than 40 researchers. We're also working with about 26 private sector companies and some public sectors." Dr. Sain is also a founding member of the newly formed Canadian Natural Composites Council.

Manufacturing biomaterials from natural fibres makes environmental sense says Dr. Sain. "Instead of using synthetic polymers and glass fibre, which are petrochemical based products we're using renewable food sources, which are all recyclable, so this has a positive environmental impact. And since the plants sequester carbon dioxide, we are storing carbon in these products, resulting in a net reduction in greenhouse gas emissions.

"There is also a tremendous savings in energy consumption because biofibres require half of the energy needed to make glass fibre." Henry Ford would undoubtedly approve. 

 

October 2003

Article by NSERC Newsbureau

Visit Dr. Sain's Web sites at: http://www.forestry.utoronto.ca/ac_staff/current/sain.html and http://www.chem-eng.utoronto.ca/faculty/sain.html.