Morphology and mechanical behavior of exfoliated epoxy/α-zirconium phosphate nanocomposites

The morphology and mechanical properties of synthetic α-zirconium phosphate (α-ZrP) based epoxy nanocomposites with 1 and 2 vol% of α-ZrP loadings were investigated. The state of exfoliation and dispersion were confirmed by X-ray diffraction and direct transmission electron microscopy imaging at various locations in the samples. Significant improvements in tensile modulus and tensile strength were observed. In this study, it is found that the fracture toughness values of the exfoliated epoxy nanocomposite systems are comparable to that of the neat epoxy. Detailed fracture mechanisms investigation indicates that no sign of crack deflection or nanoplatelet debonding is observed. Only a straight crack path is present. The nanoplatelets are broken into two halves as the crack propagates through them, indicating an existence of strong bonding between the nanoplatelet and epoxy matrix.