Preparation and mechanical properties of green epoxy nanocomposites with cellulose nanocrystals

Epoxy resin is widely used to make composites, electronic and electric parts, adhesives, and coating materials because it has excellent thermal, electrical, and mechanical properties. Using natural materials in making epoxy composites and nanocomposites would make the final products greener. Therefore, in this study, epoxidized soybean oil (ESO) and cellulose nanocrystals (CNCs) were used to make green epoxy nanocomposites. ESO was prepared by epoxidation of soybean oil with peroxyacetic acid and it was confirmed by Fourier transform infrared spectroscopy. The ESO was mixed with diglycidyl ether of bisphenol A at different weight ratios (10%–50%) and the stoichiometric amount of ethylene diamine was used for curing. CNC content in the nanocomposites was changed from 0.125 to 1 phr. Mechanical properties of the epoxy samples and the nanocomposites were investigated by universal testing machine and izod impact tester. The epoxy sample showed best mechanical properties at ESO 30%. The nanocomposite with CNC 0.25 phr showed best mechanical properties. Fracture surfaces of the epoxy sample and the nanocomposites were investigated by scanning electronic microscope. POLYM. ENG. SCI., 60:439–445, 2020. © 2019 Society of Plastics Engineers