Carboxymethyl Cellulose ‐Reinforced Polymer‐Based Matrix for Natural Fiber Composites: An Investigation Based on Surface Energy

This study investigates the behavior of natural fibers in polymer composites, focusing on enhancing adhesion through surface energy analysis. Five common natural fibers—jute, hemp, bamboo, coconut coir, and flax—embedded in an epoxy resin matrix containing an amine‐based hardener and carboxymethyl cellulose (CMC) powder as a filler have been examined. By manipulating hardener and CMC proportions while maintaining a 3:2 matrix‐to‐fiber ratio, fiber‐matrix bonding has been optimized. Surface energy calculations using the Young–Dupré equation, served as the primary parameter for assessing interfacial adhesion. Among the tested fibers, jute consistently demonstrated superior performance, exhibiting the highest surface energy and strongest interfacial bonding, particularly when CMC levels exceeded 1.5%. This synergistic effect between jute and CMC translated into composites with enhanced bonding potential and, consequently, improved performance. Findings not only confirm CMC's efficacy as a surface modifier but also highlight jute's promise as a reliable reinforcement for developing advanced, sustainable composites. These insights can contribute to ongoing efforts in designing eco‐friendly, high‐performance materials that align with both industrial needs and environmental priorities.