Sustainable 3D-Printed PLA/Graphene Nanocomposites with Enhanced Mechanical and Thermal Performance

This study investigates the mechanical & thermal properties of 3D-printed polylactic acid (PLA) composites reinforced with 0.5 wt% graphene nanoplatelets (GNPs) fabricated via single-screw extrusion & fused deposition modelling (FDM). Comprehensive characterization using SEM, TEM, EDS, FTIR, and TGA-DTA confirmed uniform graphene dispersion within the PLA matrix & adequate interfacial bonding. Mechanical testing per ASTM standards revealed significant property enhancements: tensile strength increased from 35.41 MPa to 43.43 MPa (22.7% improvement), flexural strength from 55.4 MPa to 73.27 MPa (32.3% increase), and compressive strength from 63.89 MPa to 65.54 MPa (2.6% gain). The composite maintained thermal stability with decomposition onset at 320 °C & exhibited 1–2% higher residue at 500 °C than neat PLA. TEM analysis revealed well-dispersed graphene sheets without significant aggregation, confirming the effectiveness of the processing approach. The study validates that better graphene dispersion at low concentrations can effectively enhance PLA performance while maintaining processability & cost-effectiveness for sustainable composite manufacturing.