Development and Characterization of <scp>ZnO</scp> ‐Filled and Maleic Anhydride‐Compatibilized <scp>PP</scp> / <scp>SEBS</scp> Blends for <scp>3D</scp> ‐Printing Filaments

ABSTRACT Currently, single‐screw extrusion offers a versatile and accessible route to produce polymer filaments for additive manufacturing. In this work, 1.75‐mm filaments based on polypropylene (PP)/styrene‐ethylene‐butylene‐styrene (SEBS) blends compatibilized with maleic anhydride (MA) and filled with zinc oxide (ZnO) were compounded and processed using a digitally controlled bench‐top mini‐extruder (220°C–240°C). The materials were evaluated in terms of chemical (FTIR), structural (XRD), morphological (SEM), thermal (TGA/DTA), and mechanical properties, together with filament dimensional stability and preliminary fused filament fabrication (FFF) performance. FTIR indicates interfacial interactions involving MA and ZnO, while XRD confirms preservation of α‐iPP and retention of wurtzite ZnO. Crystallinity increased from 43.6% (PP/SEBS) to 71.3% (PP/SE‐ BS/MA/ZnO). SEM analysis revealed significant refinement of SEBS‐rich domains, with the average equivalent diameter decreasing from 7.57 ± 4.79 μm to 1.34 ± 0.58 μm. TGA results show that all formulations are thermally stable within the FFF processing window, with PP/SEBS/MA/ZnO presenting the highest stability. Mechanical testing demonstrated a synergistic effect between MA and ZnO, improving strength and ductility. Preliminary FFF trials confirmed stable extrusion, consistent deposition, and good dimensional accuracy after calibration. These results demonstrate a practical small‐scale route for producing PP/SE‐BS‐based filaments with improved morphology, thermal stability, and printability.