Mechanical properties and strengthening mechanism of epoxy resin reinforced with nano-SiO2 particles and multi-walled carbon nanotubes

Highlights: • The synergistic effect of MWCNTs and nano-SiO₂ on improving the mechanical properties of epoxy resin was found. • The mechanical properties of the nano-SiO₂/MWCNTs/EP composites are excellent. • The synergistic mechanism are the micro plastic deformation, micro-cracks and their divarication, and the pull-out of MWCNTs. Nano-SiO₂ particles and MWCNTs were used to reinforce the EPs. The mechanical properties of the composites and the strengthening mechanisms of nano-SiO₂ and MWCNTs on the mechanical properties of epoxy composites were studied. The results show that the mechanical properties of the reinforced epoxy composites are greatly improved. Especially, nano-SiO₂/MWCNTs/EP composites exhibit the most excellent mechanical properties. The synergistic strengthening mechanisms of nano-SiO₂ and MWCNTs on the EP are the micro plastic deformation effect, micro-cracks and their divarication effect, and the pull-out effect of MWCNTs in EP matrix, which can reduce the extent of stress concentration and absorb more energy.