Α coherent optimization course of the silicon nitride nanofiller load in medical grade isotactic polypropylene for material extrusion additive manufacturing: Rheology, engineering response, and cost-effectiveness

Abstract

By enabling the development of complex structures with adaptable qualities, techniques for additive manufacturing have opened new routes for material development and research. In this research, silicon nitride (Si₃N₄) ceramic nanoparticles are incorporated into polypropylene (PP) matrices. Various loading levels and standardized test specimens that adhere to ASTM criteria are created. The main goal is to thoroughly characterize these composites with an emphasis on their mechanical capabilities. The rheological, thermomechanical, and morphological properties of 3D-printed PP/Si₃N₄ composites created using material extrusion (MEX) 3D printing are examined. Thermogravimetric analysis and differential scanning calorimetry are exploited to study thermal stability and phase transitions in composite materials. Mechanical testing is conducted to determine mechanical qualities, such as flexural and tensile strength and modulus of elasticity. For detailed characterization of the nanocomposites, scanning electron microscopy, and Raman spectroscopy are also performed. The results provide insight into the impact of Si₃N₄ nanoparticles on the mechanical properties, thermal stability, and rheological behavior of PP/Si₃N₄ composites. The 2 wt% Si₃N₄ filler showed overall the best performance improvement (21% in the tensile modulus of elasticity, 15.7% in the flexural strength, and high values in the remaining properties assessed). The nanocomposite with the maximum Si₃N₄ loading of wt% showed a 33.6% increased microhardness than the pure PP thermoplastic, showing a promising wear resistance for the parts built with it. This research reveals the ability of Si₃N₄ ceramic nanoparticles to improve the mechanical characteristics of PP-based compounds produced by MEX 3D printing.

Graphical Abstract