Viscoelastic performance of bagasse/glass fiber hybrid epoxy composites: effects of fiber hybridization on storage modulus, loss modulus, and damping behavior

Abstract

Abstract This study aimed to investigate the viscoelastic properties of bagasse/glass fiber multilayered hybrid reinforced epoxy composites, focusing on how fiber hybridization affects dynamic mechanical performance. Epoxy composites with various layering sequences, including all-glass (AG), all-bagasse (AB), bagasse-glass-bagasse (BGB), and glass-bagasse-glass (GBG), were fabricated and analyzed using dynamic mechanical analysis (DMA) to measure storage modulus (E′), loss modulus (E″), and damping factor (tan δ). The results showed that hybrid composites (GBG and BGB) experienced a decrease in storage modulus by approximately 25% compared to AG, indicating enhanced polymer molecular chain mobility and improved interfacial adhesion between bagasse fibers and the epoxy matrix. The glass transition temperature (Tg) was slightly lower in hybrid composites, with GBG at 61°C and BGB at 60°C, compared to 62°C for AG. In terms of energy dissipation, AG exhibited the highest loss modulus peak at 62°C, while AB showed the lowest with a Tg at 53°C. The damping factor analysis revealed that AB had the highest damping peak (tan δ = 0.9) at 61°C, although this occurred at a lower temperature than the AG composite (tan δ = 0.7 at 76°C). These findings suggest that bagasse and glass fiber hybrid composites offer tailored viscoelastic properties, making them suitable for applications in automotive components, aerospace structures, and sports equipment.