Extruded short wool fibre composites: Mechanical and fire retardant properties

Polypropylene (PP) and wool composite sheets were fabricated by continuous extrusion. Increases in mechanical properties of the composites, such as tensile modulus and strength, were achieved by adding wool and a suitable compatibiliser. Significant manufacturing parameters and desired formulations of the wool-PP composites to achieve the best possible mechanical properties were determined by Taguchi analysis. Wool characteristics within the extruded composites, namely fibre length, orientation and fracture behaviour, were also investigated by image analysis to find out their influence on the improvement of mechanical properties. Furthermore, positive effect of wool on improving fire retardancy of the composite has been identified by some preliminary flammability tests.