Abstract
This study investigates the mechanical performance and synergistic optimization of hybrid composites reinforced with alkaline-treated Enset and bamboo fibers within an unsaturated polyester matrix. To enhance interfacial adhesion, both natural fibers were subjected to a 55% sodium hydroxide (NaOH) surface treatment to remove amorphous impurities and expose reactive cellulose hydroxyl groups. Bamboo provides exceptional stiffness and tensile strength due to its high cellulose content and dense vascular bundles, while Enset fibers contribute enhanced impact resistance, flexibility, and elongation at break. Hybridization synergistically balances brittleness and flexibility. Both Enset and bamboo are rapidly renewable, eco-friendly plant resources. Unlike synthetic glass or carbon fibers, which are petroleum derived and persist in landfills, the natural fibers in this hybrid composite significantly reduce the carbon footprint and enhance the end-of-life biodegradability of the material. Utilizing a Taguchi-based Design of Experiments (DoE) coupled with Grey Relational Analysis (GRA) and Analysis of Variance (ANOVA), the study evaluates the influence of key fabrication parameters such as fiber weight fractions and stacking configurations on ultimate tensile strength, flexural modulus, impact resistance, and moisture absorption. From Taguchi analysis the optimized multi-response enset-bamboo/polyester fiber hybrid composite parameters was achieved by using the parameters are enset fiber (25%), bamboo fiber (20%), and polyester (55%) and the optimized hybrid composite formulation demonstrates superior multi-objective performance, highlighting its viability as an eco-friendly, lightweight structural substitute for traditional synthetic composites in engineering applications.