Polybenzoxazine-core shell rubber–carbon nanotube nanocomposites

This study investigated the effects of adding nano-fillers, including core shell rubber (CSR), carbon nanotubes (CNTs), and the simultaneous addition of CSR and CNT (CSR–CNT) on the curing behavior and material properties of the benzoxazine–epoxy–phenolic (BEP) ternary system. The addition of CSR and/or CNT decreased the activation energy of the BEP system and slightly increased the glass-transition temperature (Tg) of the filled systems. The addition of CNT and CSR nano-fillers increased the average toughness value of the BEP system by 14% and 61%, respectively. Moreover, the simultaneous addition of CSR and CNT further improved the toughness and flexural strength of the BEP system by 160% and 30%, respectively. Scanning and transmission electron microscopy analysis was performed to study the fracture surface and the morphology of the base BEP and its nanocomposites. The thermal stability and thermal expansion of the BEP-based nanocomposites were also investigated.