Effect of Waste Forest Content on the Mechanical and Thermal Properties of 3D Printing PLA Parts

Poly (lactic acid) is a promising biopolymer in 3D printing applications, offering a potential eco-friendly alternative to petrochemical plastics. The modification of PLA by incorporating fillers such as forest industrial residues is used to enhance its properties in line with the sustainable goals. This study aims to investigate the potential of biocomposites made of PLA with forest industrial residues such as wood ashes and wood sawdust up to 20% weight fraction and to understand the effect of fiber type and weight fraction on their thermal properties, mechanical performance and microstructure characteristics. For the thermal properties, it has been found that adding fiber decreased the thermal stability, the glass transition temperature, and the cold crystallization temperature with adding fibers but did not significantly change the melting point temperature of PLA. The crystallinity rate of PLA increased with adding filler and increasing the weight fraction up to 20%. The tensile properties highlighted a decrease in strain and tensile strength, while Young's modulus showed no clear trend. The microstructural analysis revealed that a higher filler content resulted in increased porosity, roughness, and visible pull-out fiber on both the filament and printed parts’ surface.