Characterization of 3D-Printed Polylactic Acid (PLA)–Hemp Microfiber-Reinforced Biomedical Implant Composite Material

다국어 초록 (Multilingual Abstract)

Biodegradable polymer composites have emerged as promising candidates for biomedical implantation due to their biocompatibility, tunable mechanical properties, and environmental sustainability. In this study, PLA-based composites reinforced with hemp microfibers were developed to evaluate their suitability for such applications. The research investigated the mechanical, wear, and swelling characteristics of PLA composites with varying hemp microfiber concentrations. Among the tested samples, the DH2 composite with 3 vol.% hemp microfibers displayed superior mechanical performance, achieving a tensile strength of 135.5 MPa, flexural strength of 162.0 MPa, and impact strength of 4.85 J. These improvements are attributed to enhanced stress transfer and strong interfacial adhesion between the matrix and the well-dispersed microfibers. Meanwhile, the DH3 composite, reinforced with 5 vol.% hemp microfibers, exhibited the highest hardness (98 Shore-D) and excellent wear resistance, reflected by a specific wear rate of 0.008 mm3/Nm and a coefficient of friction (COF) of 0.32. Furthermore, DH3 showed the lowest swelling tendency and in vitro mass loss against degradation, indicating superior dimensional stability and reduced moisture uptake critical traits for materials intended for implantation. In addition, the scanning electron microscope offers significant details about the morphological and microstructural analysis.