Obtenção e caracterização de filamentos para impressão 3D a partir de compósitos poliméricos de PLA e hidroxiapatita da escama do pirarucu

Abstract

The growing demand for sustainable materials has driven the development of polymer composites derived from renewable sources. In this context, this research aimed to produce and characterize composite filaments based on polylactic acid (PLA) and hydroxyapatite (HAp) extracted from the scales of the pirarucu fish (Arapaima gigas), targeting their application in additive manufacturing via fused deposition modeling (FDM). The hydroxyapatite was obtained through thermal treatment at 700 °C and characterized by TG/DTG, XRD, and FTIR, confirming its working temperature, crystalline structure, and characteristic functional groups. The filaments were processed using a single-screw extruder with HAp concentrations of 5%, 10%, and 15%, and extrusion temperatures of 190 °C and 205 °C, according to a design of experiments (DOE). Three formulations (S1, S3, and S4) resulted in continuous filaments with suitable diameters. Sample S3 (95% PLA / 5% HAp extruded at 190 °C) exhibited the best thermal, morphological, and mechanical performance. TGA/DTG thermal analysis indicated that the composites presented lower degradation temperatures compared to pure PLA (440 °C) but maintained sufficient stability for the printing process. FTIR analysis confirmed interactions between HAp and PLA. Mechanical tests revealed superior tensile strength (36.69 MPa) and hardness (70.80) for the S3 formulation, attributed to good dispersion of the ceramic filler and controlled extrusion temperature. Morphological analysis showed improved interlayer adhesion and low incidence of structural defects in this formulation. The results demonstrate the technical feasibility of using Amazonian waste as a functional reinforcement in biodegradable composites for additive manufacturing, contributing to sustainable and innovative solutions in the field of polymer materials.