Fabrication and Characterization of Kenaf and Kevlar Fibre Reinforced Graphene Filled Hybrid Composite Laminates for Engineering Applications

The present study investigates the mechanical properties of hybrid polymer composites reinforced with Kenaf and Kevlar-29 fibres, enhanced with graphene powder as a dopant. The novelty of this research lies in the synergistic combination of natural and synthetic fibres with graphene to optimize strength and hardness, providing a sustainable yet high-performance composite solution. Laminated plates were fabricated using a hand layup technique with graphene loadings ranging from 0.5 wt.% to 1.5 wt.%, and three distinct stacking configurations were explored: (1) Kenaf as outer layers with Kevlar-29 in between, (2) Kevlar-29 as outer layers with Kenaf in between, and (3) alternating Kenaf and Kevlar-29 layers. Flexural and hardness tests revealed that graphene loadings of 0.5 wt.% and 1.5 wt.% significantly improved flexural strength, particularly in Kenaf- Kevlar hybrid configurations. However, lower graphene concentrations (0.5 wt.%–1 wt.%) led to reduced hardness. The optimal performance was observed at 1 wt.%–1.5 wt.% graphene, attributed to its uniform dispersion and strong interfacial adhesion. These findings highlight the effectiveness of graphene in enhancing the mechanical properties of Kenaf- and Kevlarreinforced composites while emphasizing the importance of mitigating nanoparticle aggregation. This work provides a novel approach to balancing sustainability with high-performance reinforcement in polymer composites. Major Findings: The Graphene filler at 1 wt.%–1.5 wt.% significantly enhances flexural strength and hardness in Kenaf- Kevlar composites. However, lower graphene loadings (0.5 wt.%–1 wt.%) reduce hardness. Optimal performance is achieved through uniform dispersion and strong interfacial adhesion while avoiding graphene aggregation in the Keanf-Kevlar Hybrid Composites.