Structural and thermomechanical characterization of a new bio-epoxy composite reinforced with agave waste flower stalk fibers for sustainable applications

This study investigates the fabrication and experimental characterization of bio-epoxy (BioEP) composites reinforced with Agave americana (FSAa) fibers over a fiber loading range of 10–30 wt%. The composites were manufactured by compression molding under controlled pressure and curing conditions, after incorporating the fibers into a bio-based epoxy matrix derived from cashew nutshell liquid. A comprehensive experimental program was adopted, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) with peak deconvolution using the Asym2Sig model, thermogravimetric analysis (TGA/DTG), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), mechanical testing (tensile and flexural), and water absorption measurements in distilled and seawater based on Fickian diffusion modeling. The experimental results showed that increasing fiber content, particularly up to 30 wt% FSAa, led to improved crystallinity, thermal stability, and mechanical performance, while increasing moisture uptake, thus identifying 30 wt% FSAa as an optimal formulation for sustainable composite applications. • Elaboration and characterization a new sustainable biocomposite for the first time. • Flower stalk fibers of Agave americana waste (FS Aa ) improve fiber-matrix adhesion and reduce hydrophilicity. • Mechanical stiffness increases significantly with higher fiber content. • The thermal stability of composites is strengthened by FS Aa fiber reinforcement. • Water absorption rises with fiber loading but remains lower in seawater than in distilled water.