Influence of the extraction method of “Neuropeltis acuminatas” (NA) liana fiber for biocomposites

As part of a drive to exploit untapped local resources to replace synthetic fibers used in composite materials, a study focused on the extraction and characterization of plant fibers from “Ndik Kussa” (Neuropeltis acuminatas), a liana that grows in the wild, was done. Here we consider the hypothesis of vegetal fiber variability. Three extraction methods were studied: mechanical (manual beating), biological (simple water retting), and chemical (5% NaOH alkaline solution). This was followed by physical, chemical, thermal, and mechanical characterization of the fibers obtained after extraction. Apparent density, moisture content, and water absorption rate were determined for physical characterization. The average density, water content, and water absorption rate obtained experimentally for different NA fiber samples show variability depending on the extraction methods. The lowest apparent density of 0.24 g/cm3 is obtained by the mechanical extraction method (MEF), and the highest of 0.74 g/cm3 by the chemical extraction method (NAF). On the other hand, the highest water absorption rate of 294% is obtained for fibers extracted by the biological extraction method (RUF), and the lowest of 171% by the mechanical extraction method (MEF). The chemical composition of the fiber was analyzed by Fourier transform infrared spectroscopy (FTIR), and the thermal stability was evaluated by differential scanning calorimetry (DSC) and thermogravimetry (TGA/DTG). The mechanical properties, obtained by uniaxial tensile testing, show that the mechanical performance of NA fiber is close to that of the plant fibers used in literature to produce composite materials. Depending on the extraction process, the values for the Young modulus were 7.1GPa, 9.6GPa and 9.9GPa for NAF, RUF and MEF respectively. The highest ultimate mechanical tensile strength of 578 MPa was obtained for the biological extraction method (RUF), and the lowest of 285 MPa for the chemical extraction method.