Epoxy based hybrid nanocomposites: Fracture mechanisms, tensile properties and electrical properties

Abstract

This work explore the effect of addition of a combination of rigid nanofillers and core–shell rubber nanoparticles on the fracture mechanics, tensile, electrical and thermo-mechanical properties of epoxy resins. SiO2 nanoparticles, multi-walled carbon nanotubes (MWCNT's), as rigid nanofillers, and core–shell rubber (CSR) nanoparticles, as soft nanofillers were used with bisphenol-A based epoxy resin. Further, the rigid fillers were added systematically with core–shell rubber nanoparticles and MWCNT’s to study the combined effect of rigid nanofillers and soft CSR nanoparticles. The resulting systems will be characterized by standard methods. This includes a thorough characterization of tensile, fracture mechanics, electrical, and thermal properties. The results show that the maximum increase of fracture toughness (207%) and fracture energy (910%) was obtained for system containing 5 wt% of CSR and 10% SiO2. The electrical conductivity threshold was obtained at 0.075 wt% of MWCNT’s modified system. The introduction of CSR nanoparticles significantly increase the fracture energy of the matrix with decrease in tensile strength and tensile modulus, which was further recovered with the addition of SiO2 nanoparticles. The analysis of the fracture surfaces revealed the toughening micro-mechanisms.