The defense will take place in the Josette Genevois amphitheater, under the supervision of Ms. Olga KLINKOVA (ISAE-Supméca, Euler Laboratory).
The thesis research focuses on thermoplastic biocomposites reinforced with short Alfa fibers. The objective is to link the formulation, processing, and microstructure to the mechanical, thermal, hygrothermal, and surface properties of these materials.
Alfa/LDPE composites are produced by twin-screw extrusion and injection molding. Their properties are characterized for various fiber contents and compared with micromechanical models to identify the fiber/matrix interface as a control variable.
At the structural level, a design and optimization approach for Alfa/LDPE/PU sandwich panels is presented, combining thermomechanical calculation, experimental design, neural networks, and hybrid optimization.
Surface behavior is analyzed through instrumented micro-scratching, and hygrothermal durability is evaluated by immersion until saturation. The study examines water absorption, anisotropic swelling, and performance evolution after aging.
The manuscript aims to establish an integrated framework for design, where controlling the fiber/matrix interface governs both the performance and durability of the materials.
