Reinforcement Fibres

Our reinforcement materials are natural plant fibres, which also have the advantage of being able to biodegrade. Hemp and flax are both relatively cheap fibres that do not require much preparation and can be grown with little negative environmental impact, unlike cotton, which requires a large amount of pesticides, or wood pulp, which is not completely sustainable. Pomelo skins and onion peels are both considered waste and would otherwise serve no useful purpose. We have also used human hair, to determine whether animal fibres would also be compatible with the cellulose acetate matrix.

Our chosen method of reinforcement is the anisotropic short fibre method, which involves cutting up the fibres into short pieces and mixing them randomly throughout the entire composite. Research has shown that unidirectional continuous fibre reinforcement is the strongest type of reinforcement, but these take much more effort to produce and are higher in cost. It was difficult to produce continuous fibre reinforced composites at our school lab without advanced equipment, which we were unable to obtain. The short fibre reinforcement has a lower fibre to matrix ratio and is easier to produce than other methods.