Mitsubishi Motors, with cooperation from the Aichi Industrial Technology Institute, has developed an automotive interior material which uses a plant-based resin, polybutylene succinate (PBS), combined with bamboo fibre. Parts made from the material will be used in the interior of a new-concept minicar, to be launched in Japan in 2007.
Mitsubishi has dubbed its plant-based resin technology, including this PBS-bamboo fibre resin, “Green Plastics”. The Japanese motor giant plans to substitute plant-based resins and quick-growing plant fibres for materials such as petroleum-based resins and wood hardboards used in car interiors. Mitsubishi says the use of these renewable plant-based resources, which it has been developing since 2004, will add no CO2 to the atmosphere.
PBS, the main component of the material, is a plant-based resin composed mainly of succinic acid and 1,4-butanediol. The succinic acid for the material will be created through the fermentation of sugar extracted from sugar cane or corn. The new material combines bamboo fibre with PBS in order to increase its rigidity.
Bamboo grows to its full height in just a few years, compared with the tens of years required for traditional timber, and as such can be considered a sustainable resource. Bamboo is available and can be grown in a wide variety of areas including Japan, China, and Southeast Asia. The use of Green Plastics may lead to further breakthroughs in the use of bamboo.
According to tests, this PBS/bamboo-fibre prototype achieves an estimated 50 per cent cut in lifecycle CO2 emissions over polypropylene, a widely used petroleum-based plastic. VOC (volatile organic compounds) levels are also reduced drastically - roughly 85 per cent in testing - over processed wood hardboards.