Why natural fibres?
A high-tech choice
Fibres that give strength and stability to plants are being incorporated in an ever widening range of industrial products
Natural fibres have instrinsic properties – mechanical strength, low weight and low cost – that have made them particularly attractive to the automobile industry. In Europe, car makers are using mats made from abaca, flax and hemp in press-moulded thermoplastic panels for door liners, parcel shelves, seat backs, engine shields and headrests.
For consumers, natural fibre composites in automobiles provide better thermal and acoustic insulation than fibreglass, and reduce irritation of the skin and respiratory system. The low density of plant fibres also reduces vehicle weight, which cuts fuel consumption. For car manufacturers, the moulding process consumes less energy than that of fibreglass and produces less wear and tear on machinery, cutting production costs by up to 30%.
The use of natural fibres by Europe’s car industry is projected to reach 100 000 tonnes by 2010. German companies lead the way. Daimler-Chrysler has developed a flax-reinforced polyester composite, and in 2005 produced an award-winning spare wheel well cover that incorporated abaca yarn from the Philippines. Vehicles in some BMW series contain up to 24 kg of flax and sisal.
Japan’s carmakers, too, are “going green”. In Indonesia, Toyota manufactures door trims made from kenaf and polypropylene, and Mazda is using a bioplastic made with kenaf for car interiors.
Worldwide, the construction industry is moving to natural fibres for a range of products, including light structural walls, insulation materials, floor and wall coverings, and roofing. Among recent innovations are cement blocks reinforced with sisal fibre, now being manufactured in Tanzania and Brazil.
In India, a growing shortage of timber for the construction industry has spurred development of composite board made from jute veneer and coir ply – studies show that coir’s high lignin content makes it both stronger and more resistant to rotting than teak. In Europe, hemp hurd and fibres are being used in cement and to make particle boards half the weight of wood-based boards.
Geotextiles are another promising new outlet for natural fibre producers. Originally developed in the Netherlands for the construction of dykes, geotextile nets made from hard natural fibres strengthen earthworks and encourage the growth of plants and trees, which provide further reinforcement. Unlike plastic textiles used for the same purpose, natural fibre nets – particularly those made from coir – decay over time as the earthworks stabilize.