Optimization and Characterization of Recycled Polypropylene and Date Palm Nanocomposites for 3D Printing Applications

Recent advancements in additive manufacturing have created new prospects for producing biocomposite materials; however, challenges persist in the attainment of sustainable and efficient manufacturing methods. Additionally, 3D printing still has limitations such as suboptimal mechanical properties and processability issues. In this study two main objectives are addressed. First, the properties of bionanocomposites made from recycled polypropylene and date palm nanofillers were experimentally investigated using hot melt extrusion to identify the optimal nanofiller content in the polymer matrix. Second, the effects of the 3D printing parameters on the mechanical performance of these innovative materials were evaluated. The mechanical properties (tensile strength, flexural strength, and modulus of elasticity) and physical properties (water absorption) of the extruded materials were thoroughly evaluated, and the tensile strength was the primary focus for optimizing the 3D printed samples. The highest tensile (25.5 MPa) and flexural (50.6 MPa) strengths were achieved with a 3% wt. nanofiller content. To facilitate 3D printing, filaments were produced from the bionanocomposite via a single-screw extruder. The key printing parameters of the nozzle temperature (250 degrees C and 270 degrees C), printing speed (60 mm/s and 80 mm/s), and layer thickness (0.1 mm and 0.3 mm) were optimized via the design of experiment (DoE) methodology. The optimal settings were a nozzle temperature of 270 degrees C, printing speed of 60 mm/s, and layer thickness of 0.1 mm. Under these conditions, the highest tensile strength of the 3D-printed samples was 22 MPa; this value was in close agreement with the strength of the extruded material. This research contributes to sustainable manufacturing by providing valuable insights into the fabrication and performance of bionanocomposites for 3D printing applications.