An Investigation of the Mixing Design and the Mechanical Properties of Glass and Date Palm Fibers and Nanoparticle-Polyester Hybrid Composites

This study investigates, in the first stage, the mechanical properties of Glass Fiber (GF) and Date Palm Fiber (DPF)-reinforced polyester hybrid composites. Specimens were prepared with volume compositions of GF:DPF at 100:0%, 75:25%, 50:50%, 25:75%, and 0:100%. The results showed that the best Ultimate Tensile Strength (UTS) (23.00 MPa) was obtained for the 50:50% composition, while the highest absorbed energy (E-absor) in the impact test (3.76 J) was recorded for the 100:0% composition. In the second stage, the mechanical properties were further improved by incorporating nanoparticles: Carbon Nanotubes (CNT), Alumina (Al₂O₃), and Silica (SiO₂). A Design of Experiments (DOE) approach was carried out based on the best mechanical results, using ten nanoparticle-doped specimens. The mixing method in Minitab 17 software was used to identify the optimal combination, which was 88% CNT and 12% Al₂O₃. Consequently, the tensile strength increased to 35 MPa, and the (E-absor) reached 4 J.