Caractérisation des comportements physique et mécanique de biocomposites composés d'une matrice de polyéthylène végétale haute densité renforcée par des fibres de bambou : Influence des traitements physiques et chimiques des fibres sur les propri

The environmental concern with the unregulated use of non-renewable resources, as well as the inadequate disposal of waste in the environment, encourage the development of awareness measures and technological alternatives. Faced with this problem, there is a need to manufacture products that are less aggressive to the environment, either according to their raw material, from a renewable resource, or according to their post-utilization. Thus, the use of natural fibers applied as reinforcement in polymeric matrices presents itself as a highlight in the scientific environment. In this context, the proposal of this thesis was to evaluate and intensify the adhesion between bamboo fibers and green polyethylene matrix, in order to produce polymeric composites with good mechanical resistance to be applied in fairing and internal car finishes. In addition to the concern of using a reinforcement with high mechanical strength and natural source, this work also proposes the use of a polymeric matrix produced from a renewable plant source, sugarcane, which, in sum, promotes the capture and fixation of CO2. Physical-chemical, morphological and mechanical properties of the bamboo fibers were evaluated to analyze the effect of applied surface treatments. The physico-chemical parameters presented a decrease in fiber mass after treatments, as well as variations in density, porosity and pore size. The morphological evaluation showed an increase of roughness in the fibers surface, indicating a good mechanical anchorage by the polymer matrix. The results of the mechanical efficiency of the fibers showed a considerable increase of the maximum supported tension and the elasticity modulus. The characterization of the composites showed that the treatments were effective for a good adhesion between fiber and polymer matrix, indicating that the best treatments were mercerization and acetylation, and that the best conformation was the use of unidirectional long fibers (direction of the mechanical request) and continuous. The results were effective for its application.