# The effect of chemical surface treatment on the fracture toughness of microfibrillated cellulose reinforced epoxy composites

• Yeo, Jun-Seok (Department of Polymer Science & Engineering, Dankook University) ;
• Kim, Oh Young (Department of Polymer Science & Engineering, Dankook University) ;
• Hwang, Seok-Ho (Department of Polymer Science & Engineering, Dankook University)
We conducted the surface modification of a microfibrillated cellulose (MFC) as a reinforcing filler of epoxy resin with triethoxy(3-glycidylpropyl)silane (GPS) to increase the mechanical properties of epoxy composite. The chemical modification for the surface of pristine MFCs was confirmed by FT-IR and SEM/EDX. Two different epoxy composite series were prepared using the pristine MFCs and GPS-modified MFCs (GPS-MFCs) to investigate the mechanical properties and fracture toughness of the epoxy composites according to the cellulosic filler contents. The tensile and impact properties of the epoxy composites showed the better performance of GPS-MFC/epoxy composites than of the pristine MFC/epoxy composites. The results of the critical stress intensity factor ($K_{IC}$) and the critical strain energy release rate ($G_{IC}$) show the improved interfacial adhesion between epoxy matrix and cellulosic filler in the GPS-MFC/epoxy composites, and their enhanced fracture toughness.