Long, natural fibres key to composites made only from renewable resources

Advances in Textiles Technology, Nov, 2008

The first generation of high-performance composites made from completely biodegradable natural fibre-reinforced plastics has been produced by a UK-based consortium. Exploiting long, aligned natural fibres to reinforce naturally derived plastics, these fabric-based materials are believed to be the first of their kind.

Undertaking the work is Combine--a UK-based collaborative project co-funded by the Technology Strategy Board, whose objectives are to develop high-performance bio-derived composites for structural applications. The two-and-a-half-year project says it has now developed the first generation of materials, with plans underway to manufacture three industrial demonstrator parts.

Two end-user partners within the consortium, Fairline Boats of Peterborough, UK, and Lightweight Medical of Glasgow, UK, have begun to develop a marine component and a section of a mobile incubator, respectively. An opportunity has recently arisen for a UK-based moulding company or end-user to join the project and to assist with the development of the case study parts.

Natural fibres are already being used to reinforce conventional plastics; for example, in injection-moulded or press-moulded interior parts for the automotive industry. However, the natural fibres are generally short and randomly oriented, so their use is limited due to the relatively low mechanical properties obtained. Plastics made from renewable resources are even further from market when it comes to their use in engineering products.

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

Polylactic acid (PLA), a bio-plastic made from corn, has been identified as a suitable matrix material by the consortium, while polypropylene (PP) is also being considered as a partial nearer-to-market solution. These are then combined with the natural fibre reinforcements of choice--flax and hemp fibre--both easily grown in the UK.

Novel spinning and weaving techniques are being developed to optimize material properties. Future work will include process optimization, painting, bonding and moulding.

In addition to Fairline Boats and Lightweight Medical, the consortium consists of seven other UK partners:

* The Queen Mary University of London;

* Springdale Natural Products;

* E&F Composites of Hartlepool;

* John L. Brierley of Huddersfield;

* Sam Weller and Sons of Huddersfield;

* NetComposites (the project co-ordinator) of Chesterfield; and

* Tilsatec of Wakefield.

For further information, contact: Combine, c/o Gordon Bishop, Managing Director, NetComposites Ltd, Tapton Park Innovation Centre, Brimington Road, Chesterfield, S41 0TZ, UK; tel: 1246-541918; fax: 1246-563322; E-mail: gordon.bishop@netcomposites.com; http://www.combineproject.org.uk