Polylactic acid filaments reinforced with natural fique fibers for 3D printing applications

3D printing offers advantages in terms of geometry customization and material waste reduction; however, the formulation of polymeric composite materials with improved mechanical properties remains a challenge. This study analyzes the use of natural fique fibers as reinforcement in polylactic acid filaments for additive manufacturing applications. In order to improve their compatibility with the polymer matrix, the fibers were subjected to an alkalization treatment and then incorporated into the polylactic acid at a 10 wt. % using a single-screw extruder. The composite filament was characterized by scanning electron microscopy for morphological analysis, differential scanning calorimetry, and thermogravimetric analysis. The test specimens for mechanical evaluation were manufactured by 3D printing and subjected to tensile testing according to ASTM D638-22 using a universal testing machine. In addition, statistical analysis was performed using ANOVA to determine the significance of the differences between pure polylactic acid and the reinforced composite. The differential scanning calorimetry results showed an increase in the glass transition temperature and cold crystallization temperature due to the incorporation of the fibers. Thermogravimetric analysis showed lower thermal stability of the composite, reflected in a reduction in the degradation temperature. Morphological observations indicated low interfacial adhesion between the fibers and the matrix, which contributed to the decrease in tensile strength. However, the composite material had a higher modulus of elasticity, indicating an increase in structural rigidity.