Hybrid Polypropylene Biocomposites Reinforced with Short Man-Made Cellulose Fibres and Softwood Flour—Optimisation of Properties Using Response Surface Methodology

Wood-polymer composites and composites reinforced with natural and man-made cellulose fibres are being extensively used in the automotive and building industries. The main shortcoming of the former is their low-impact resistance and brittleness. The relatively high cost of natural and cellulose fibres is the limitation of the latter. This research uses a hybrid combination of wood flour and short man-made cellulose fibres to develop polypropylene composites for injection moulding that excel in mechanical characteristics and have low material cost. Both reinforcements are of wood origin. The synergistic hybrid effect of this combination of reinforcements helps to achieve their mechanical performance superior to that of wood-polymer composites at preserved low cost. The proposed Response Surface Methodology enables the calculation of necessary weight fractions of two reinforcements to achieve desired mechanical properties like strength, tensile, flexural modulus, and impact resistance.