Polymer Composites, cilt.46, sa.16, ss.15369-15380, 2025 (SCI-Expanded, Scopus)
In this study, the effect of graphene nanoparticles (GnPs) on the mechanical properties of hemp fiber reinforced epoxy composites was investigated. The composites were prepared using the vacuum assisted resin transfer molding (VARTM) method and prepared with graphene nanoparticles at 1%, 2%, and 3% weight ratio. The mechanical performance of the composites was evaluated by tensile, flexural, and Charpy impact tests. Tensile test results showed that the addition of graphene nanoparticles increased tensile strength and Young's modulus but decreased elongation at break. The highest tensile strength was obtained in the composite containing 2 wt% GnP (64.809 MPa). The flexural test results also showed a similar trend, with the highest flexural strength (82.27 MPa) and flexural modulus (4.63 GPa) observed in the composite containing 2 wt% GnPs. However, composites containing 3 wt% GnPs showed a slight decrease in mechanical properties due to agglomeration. Fracture surface analysis showed that graphene nanoparticles improved fiber–matrix interfacial bonding and provided a more consistent fracture mode. However, agglomeration and delamination were observed at high graphene concentrations. These findings underscore the critical role of GnPs concentration in balancing reinforcement efficacy and dispersion quality, with 2 wt% identified as the optimal loading, providing actionable insights for designing high-performance natural fiber composites through nanomaterial integration.