As Van Wees also embraces the growing awareness of environmental sustainability, a bio-based composite must be included in its range.
Flax was chosen as natural fibre for a composite particularly attractive for interior applications because of its warm and elegant appearance. Although thermoplastics are available that should be CO²-neutral, polypropylene was selected as matrix material because of its better mechanical and processing properties, resulting in a composite of higher quality. For example, this is illustrated by the fact that its specific modulus is even higher than the Glass/PP-one. Compared with other companies which adopted the same fibre/matrix-combination, the crossply laminate is perfect for the market. With its bending strength and modulus of 150 MPa and 16 GPa respectively, it is far superior to products such as Biotex® (79 MPa, 4.5 GPa) and Lincore® (55 MPa, 6.1 GPa).
Apart from creating a complete panel from this UD, it can also be used for laminating a core material like cork or balsa wood to give it strength, rigidity and a decorative Technicum surface. Because of its low fibre weight of only 100 g/m², a few UD layers can already improve the mechanical properties of such a sandwich structure considerably.
For our stand at JEC we have produced a number of floor tiles composed of Flax PP Crossply, with 5 millimetre PP panel as the core material. In recent months we have also produced PLA based UD flax composites and the results are comparable to the PP resin based materials. Finally, to facilitate composite techniques such as resin injection or resin transfer moulding, the flax can be patterned to a UD that is held together between adhesive scrims or by means of a binder that is compatible with thermoset matrices.
In other words, UD and Crossply technology creates new options for bio-based composites which are particularly appropriate for industrial implementation and can therefore create economically viable green alternatives for the current mass production of plastics and laminates.