Corvallis, Oregon – Researchers at Oregon State University have found that cellulose made from plant fibres has the potential to be used as a silica substitute in tires, possibly increasing their fuel efficiency and reducing energy costs.
The researchers said that microcrystalline cellulose, a product that can be made easily from almost any type of plant fibre, could partially replace silica as a reinforcing filler in the manufacture of rubber tires. Early tests have indicated that, compared with conventional tires, the cellulose tires would have comparable traction on cold or wet pavement, be just as strong, and provide even higher fuel efficiency in hot weather.
“We were surprised at how favourable the results were for the use of this material,” said Kaichang Li, associate professor of wood science and engineering. “This could lead to a new generation of automotive tire technology, one of the first fundamental changes to come around in a long time.”
Cellulose fibre has been used for some time as reinforcement in some types of rubber and automotive products, such as belts, hoses and insulation, but never in tires, where the preferred fillers are carbon black and silica. However, carbon place is made from oil, while silica processing is energy intensive, and both products are very dense and reduce the fuel efficiency of automobiles.
In the study, the researchers replaced up to about 12 per cent of the silica used in conventional tire manufacture, which decreased the amount of energy needed to compound the rubber composite, improved the heat resistance of the product, and retained tensile strength.