Development, characterization, and mechanical, dynamic mechanical, and hydrophilic studies of a sustainable Aquilaria agallocha gum-filled epoxy hybrid biocomposite reinforced with hemp and snake grass fibers.

Natural fiber-reinforced epoxy composites are increasingly popular as eco-friendly alternatives to synthetic materials due to their low density, biodegradability, and renewability. In this investigation, a unique hybrid epoxy biocomposite was produced using Aquilaria agallocha gum as a biofiller and snake grass and hemp fibers as reinforcement. Hand lay-up followed by compression molding was used to create composites with 15 vol% biofiller and varying fiber contents (5-30 vol%). A systematic study was conducted to determine how adding hybrid fiber affects mechanical, dynamic mechanical, water absorption, and biodegradation properties. At 20 vol% fiber loading, tensile strength peaked at 29.2 MPa, while impact strength peaked at 25 vol% with 2.7 kJ m-2. At 30 vol% fiber concentration, the highest flexural strength was 41.72 MPa. Dynamic mechanical analysis showed an increase in glass transition temperature to ∼80 °C and a rise in storage modulus up to ∼6.5 × 109 Pa, suggesting improved fiber-matrix interactions and restricted polymer chain mobility. The inclusion of hydrophilic natural fibers was shown to result in controlled moisture absorption and partial biodegradation, as demonstrated by soil burial and water absorption tests. Effective fiber dispersion, interfacial adhesion, and synergistic hybridization effects are responsible for the improved characteristics. The produced composite shows promise for use in lightweight, sustainable structural applications that require a low carbon footprint, moderate strength, and ecological compatibility.