Physico-mechanical behaviour of Oil Palm Broom Fibres (OPBF) as eco-friendly building material

Until recently, the rib of the leaflets of the oil palm tree was only used for making brooms due to its stiffness and durability. However, the mechanical properties of this fibre are unknown. Due to the geometrical variation of the cross-section of the fibres along their length, this study divided them into 4-categories. The result of this study reveals that the fibres have a specific gravity between 0.45-0.84 and diameter varying between 0.20 mm (at the tail) and 4.00 mm (at the cap). Maximum tensile strength of 900 MPa was recorded. Scanning electron microscopy of fibre cross-sections revealed graded cavities concentrated at the core but a densely packed cortex. This radial and longitudinal density gradient is responsible for the phenomenon whereby the fibres are stiffer in bending but possess reduced tensile strength towards the cap. Further investigations carried out on the fibres include water absorption, chemical composition and thermogravimetric analysis. The fibre is proposed for use as natural-fibre reinforcement in cement and polymeric composites as it is cheap, and void of high carbon footprints associated with the use of conventional reinforcement materials in construction.