Synthesis of Eggshell Membrane‐Derived Carbon Dots for Enhancing Mechanical Properties of Glass Fiber Composites

ABSTRACT This study investigates the transformation of eggshell waste into Eggshell Membrane Carbon Dots (ESM‐CDs) as sustainable nanofillers for reinforcing glass fiber/epoxy polymer composites, aligning with circular economy and green engineering principles. The research focuses on synthesizing ESM‐CDs via hydrothermal carbonization, integrating them into an epoxy matrix, and evaluating their impact on the mechanical performance and sustainability of polymer composites. While synthetic nanomaterials have been widely explored for composite reinforcement, the potential of waste‐derived ESM‐CDs in polymer composites remains underexplored. This study addresses this gap by demonstrating the dual benefits of waste‐derived nanomaterials: enhanced mechanical properties and reduced environmental impact. ESM‐CDs were synthesized, uniformly dispersed into the epoxy matrix at varying concentrations (up to 4 wt.%), and incorporated into glass fiber composites with 90° fiber orientation. Mechanical testing revealed significant improvements: tensile strength increased by 14.06%, and flexural strength surged by 35.08% at 4% ESM‐CD loading. These enhancements are attributed to improved fiber‐matrix adhesion and matrix‐dominated properties, which contribute to increased durability and extended lifecycle performance of the polymer composites. Scanning Electron Microscopy (SEM) analysis provided critical microstructural insights, showing that ESM‐CD‐reinforced composites exhibited uniform nanofiller dispersion, reduced void content, and stronger interfacial bonding compared to the void‐prone base composites. This research highlights the potential of ESM‐CDs as sustainable, high‐performance nanofillers for advanced polymer composites, offering a scalable solution for structural applications. By integrating waste‐derived nanomaterials, this study also focuses on the broader goals of green technology and sustainable development, paving the way for innovative, eco‐friendly material solutions.