The effect of block copolymer and core-shell rubber hybrid toughening on morphology and fracture of epoxy-based fibre reinforced composites

The toughening performance of hybridized core-shell rubber particles and block copolymers on bulk epoxy and epoxy based carbon fibre reinforced composites was investigated. The results reveal that the interlaminar fracture toughness of the fibre reinforced laminates increased by more than 300% due to an enhanced fibre-matrix adhesion because of a combination of BCP and CSR particles. However, no synergistic improvement of the fracture mechanics properties of the bulk materials was found. Thereby, the critical energy release rate of the bulk and fibre reinforced materials is related to the interparticle distance to particle size ratio of the modifiers in the bulk/matrix systems and the plastic zone size. Furthermore, the fibre volume content of the CFRP influences the final BCP phase morphology, and thus the fracture toughness.