Fracture toughness of vapor grown carbon nanofiber-reinforced polyethylene composites

Abstract

The impact fracture behavior of a vapor grown carbon nanofiber (VGCNF) reinforced high-density polyethylene (PE) composite was evaluated. The samples consisting of pure PE and composites with 10wt and 20wt of VGCNFs were prepared by a combination of hot-pressing and extrusion methods. Extrusion was used to produce samples with substantially different shear histories. The fracture behavior of these samples was analyzed using the essential work of fracture (EWF) approach. The results showed an increase of 292 in the essential work of fracture for the loading of 10wt. Further increasing fiber loading to 20wt caused the essential work of fracture to increase only 193 with respect to the unmodified material. Evaluation of the fracture surface morphology indicated that the fibril frequency and microvoid size within the various fiber loadings depended strongly on processing conditions. © 2009 A. R. Adhikari et al.