Eggshell reinforced biocomposite-An advanced green alternative structural material

The need for bio-based polymers as substitutes to recalcitrant petroleum sourced plastics is ever growing, because of increase in demand globally. Eggshell nanopowder (ENP) prepared using mechanical attrition and ultrasound irradiation was used to infuse a bio-based polymer [ Super Sap 100/1000 epoxy (SSE)] for possible enhancement of its mechanical properties. The ENP, neat SSE and SSE/ENP composites were characterized using X-ray Diffraction, Transmission Electron Microscopy (TEM), Energy dispersive spectroscopy (EDS), Scanning Electron Microscopy, Thermogravimetic Analysis (TGA), Dynamic Mechanical Analysis (DMA), Thermomechanical Analysis (TMA) and flexure analysis. TEM and EDS analysis showed evidence of ENP in the SSE matrix whiles DMA and TMA analysis revealed significant improvements (7-22%) in the storage moduli and (3-17%) in coefficient of thermal expansion (CTE) respectively. Also, major delay in 5% decomposition temperatures and increases in char yields were observed in TGA analysis. The flexure strength, modulus, and toughness significantly improved by 6-31%, 11-37%, and 10-36%, respectively. Microstructure of fractured surfaces showed deflected crack paths which contributed to improve toughness. (c) 2015 Wiley Periodicals, Inc.