S. SAMANKAN - Fatigue and Fracture Laboratory, Department of Mechanical Engineering, Iran University of Science and Technology, Narmak, Tehran, ۱۳۱ ۱۴-۱۶۸۴۶, Iran
M. R. AYATOLLAHI - Fatigue and Fracture Laboratory, Department of Mechanical Engineering, Iran University of Science and Technology, Narmak, Tehran, ۱۳۱۱۴-۱۶۸۴۶, Iran
S. SHADLOU - Fatigue and Fracture Laboratory, Department of Mechanical Engineering, Iran University of Science and Technology, Narmak, Tehran, ۱۳۱۱۴-۱۶۸۴۶, Iran

In the recent years Multi-walled carbon nanotubes (MWNTs) have stimulated great interest in the field of polymer composite materials, owing to their marvelous multi-functional characteristics such as very large aspect ratio and high stiffness. This study aims to understand the link between the nature of polymer as the base material for nanocomposite and reinforcement role of MWNTs. For this purpose, three common polymers, with high industrial applications, namely vinyl ester, polyester and epoxy were chosen. The standard tensile and fracture specimens were prepared for both neat and reinforced resins using 0.5wt% of MWNTs. The results indicated that while for vinyl ester and polyester resins, there was no improvement in elastic modulus, for epoxy resin the elastic modulus increases by 5.6% with addition of MWNTs. The ultimate strength of all three nanocomposites was less than that of neat resins. The fracture toughness of both vinyl ester and polyester nanocomposites, which were measured utilizing single-edged notch bend (SENB) specimens, showed considerable improvement compared to those of neat resins, but decreased a little for epoxy specimens. Several optical microscopy pictures were taken from the fracture surfaces to evaluate the surface features, fracture mechanisms.

Tensile properties, fracture toughness, thermosetting polymer, MWNTs