Effet du traitement chimique et thermique d’un composite (Polyacide lactique (PLA)/Ampélodesmos mauritanicus (Diss)

Abstract

This research studied the effect of thermal and chemical modification with citric acid on the adhesive properties of a composite based on poly (lactic acid) and Ampelodesma mauritanica fibers. Biocomposites containing 20% by weight of fibers were prepared using a palatograph. Treated and untreated fibers were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Citric acid treatment reduced hemicellulose, lignin and wax content, as indicated by the disappearance or attenuation of absorption bands at 1650 and 1731 cm-1 in FTIR. This treatment also improved the thermal stability and roughness of Diss (Ampelodesma mauritanica) fibers compared with untreated and thermal treated fibers. Mechanical tests on composites reinforced with these fibers revealed that treatment with 5% citric acid increased modulus of elasticity (4.680 GPa), tensile strength (48.90 MPa) and elongation at break (2.52%) compared with untreated and thermal treated composites. These observations were corroborated by scanning electron microscopy.