Sisal fiber as sustainable reinforcement in composite applications: a comprehensive review

The construction industry is increasingly seeking sustainable materials to mitigate environmental impacts. This review examines the potential of sisal fiber composites as reinforcement for building components. Valued for their low density (1.3–1.5 g/cm3), high tensile strength (10–700 MPa), and good thermal/acoustic insulation, sisal fibers are a promising alternative to synthetics. The review covers fiber origins, composition, and the critical role of surface treatments. Alkali treatment increases tensile strength by 10.8%, while silane treatment reduces moisture content from 12.8% to 1.7%. Acetylation boosts tensile strength by 30% and reduces fiber diameter by 20%. The suitability of various polymer and cement/concrete matrices is discussed, with microstructural analysis (scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy) confirming improvements. Life cycle assessment shows a 20% lower global warming potential against glass fiber composites. Future focus on scalability, standardization, and enhanced functionalization is essential to realize sisal fiber-reinforced composites’ full potential as eco-friendly reinforcements.