Mechanical and thermal properties of sisal fiber reinforced acrylated epoxidized castor oil toughened diglycidyl ether of bisphenol A epoxy nanocomposites

In this study, the bio-based epoxy nanocomposites were prepared from acrylated epoxidized castor oil toughened diglycidyl ether of bisphenol A epoxy network filled with sisal fibers and cloisite 30B clay. The chemical structure of acrylated epoxidized castor oil resin was confirmed by Fourier transform infrared and Proton nuclear magnetic resonance (¹HNMR) spectroscope techniques. Mechanical and thermal properties of the sisal fiber reinforced acrylated epoxidized castor oil toughened diglycidyl ether of bisphenol A epoxy composites and nanocomposites were investigated. Mechanical tests revealed that bio-based epoxy nanocomposites (containing 80% diglycidyl ether of bisphenol A/20% acrylated epoxidized castor oil / 30% treated sisal fiber/ 1% cloisite 30B weight ratio) were found to be higher in tensile strentgh to 78%, flexural strentgh to 44% and impact strength to 20% than the 80% diglycidyl ether of bisphenol A/20% acrylated epoxidized castor oil matrix. Thermogravimetric analysis results showed that the thermal stability of diglycidyl ether of bisphenol A /acrylated epoxidized castor oil matrix increased with the incorporation of alkali-silane-treated sisal fiber and cloisite 30B nanoclay. The apparent activation energy was increased from 236 to 273 KJ/mol with the addition of 1% cloisite 30B clay and 30% alkali-silane-treated sisal fiber to the 80% diglycidyl ether of bisphenol A /20% acrylated epoxidized castor oil matrix. Scanning electron microscopy was performed to investigate the fracture behaviour at the fiber-matrix interface.