Natural fibres are already being used to reinforce conventional plastics in, for example, the automotive industry. However, natural fibres are generally short and randomly oriented with limited use due to the relatively low mechanical properties obtained.

The COMBINE project is converting natural fibres into long, aligned reinforcements to exploit the inherent and mechanical properties of plants in structural applications, with the added advantage of having a lower weight than conventional reinforcement such as glass fibre.

The consortium has identified polylactic acid (PLA), a plastic made from corn, as a suitable matrix material. Popypropylene (PP) is also being considered as a partial nearer-to-market solution.

These are combined with natural fibre reinforcements such as flax and hemp. Spinning and weaving techniques are being developed to optimise material properties, and further work will include process optimisation, painting, bonding and moulding.

COMBINE’s objectives are to develop high performance bio-derived composites for structural applications. The project is co-financed by the UK Technology Strategy Board. The two-and-a-half year programme is half way through and now plans to manufacture three industrial demonstrator parts.

COMBINE partners Fairline Boats and Lightweight Medical have already begun to develop a marine component and a section of a mobile incubator respectively. Other UK partners are Queen Mary University of London, Springdale Natural Products, E&F Composites, John L Brierley, Sam Weller and Sons, NetComposites (project coordinator) and Tilsatec.