Elaboration et caractérisation de composites bio-sourcés à base de fibres de palmier dattier.

Abstract

The availability and price of raw materials is critical to the success of any industrial project, therefore many researchers are working to find alternative materials at low prices through the use of natural waste or recycling. The date palm tree produces enormous quantities of dry palms every year in the form of waste left over during its growth and natural evolution. The recycling and exploitation of this waste instead of burning it would help to convert the vegetable waste into a real wealth that can be used effectively and with respect for the environment. In this context, this study includes an experimental component that consists of physical-mechanical characterization of the raw material (Palm), elaboration and mechanical characterization of biocomposites and development and study of the behavior (overall stiffness DG) of sandwich structure beams. The study was started by characterizing a major component of the palm date tree that is the mature palm. The palm being decomposed into essentially two parts, Petiole and Rachis, the characterization was then carried on the fibrous wood and the fibers of these two parts. The physical characterization will concern the density of the fibers and the vegetal matrix (lignin) as well as the moisture content in the different parts of the palm. The mechanical tests made it possible to determine the mechanical characteristics of the fibrous wood and fibers extracted from both parts of the palm after drying. At the end of this study, the results obtained show the influence of the position of the tested sample on the physico-mechanical properties. They also made it possible to situate this type of fibrous wood and these fibers among other results of the scientific literature and to consider using them in the implementation of composite materials and in insulation elements. The mechanical characterization of the composite materials based on these fibers was carried out by the use of two different types of matrix (epoxyde, polypropylene). Tensile tests carried out for composites at different fiber percentages (4, 7, 10 and 15%), reveal that there is an improvement in the mechanical properties of the virgin matrix proportional to the mass content of fibers. Compression tests on composite materials based on petiole wood particles and natural matrix showing the isotropic and anisotropic characteristics of these tested materials. The results obtained are used to valorize this waste for possible industrial applications. The value of the overall stiffness of the wood particle core sandwich is high relative to the heart of the raw petiole wood. The overall stiffness in palm-based wood sandwich is higher compared to sandwich with agglomerated cork core. The macroscopic observation of fracture facies shows the good adhesion between the skins and the heart. This is due to the method used in the preparation of sandwich structure.