Investigating mechanical properties of epoxy/organoclay nanocomposites

Abstract

This study aims to investigate the organoclay effect on the mechanical properties of epoxy nanocomposites. In order to characterize the organoclay effect, three different loadings of organoclay, 2.5, 5, and 7.5 wt%, were dispersed into the epoxy with a mechanical blender followed by sonication. Tensile tests and fracture tests were carried out on these specimens to determine their stiffness, strength and fracture behaviors. The experimental results obtained from tensile tests indicate that the stiffness of the epoxy increases with the increment of organoclay inclusion; however, the corresponding failure strain decreases. On the other hand, fracture tests on single- edge-notch bending specimens reveal that the inclusion of organoclay may dramatically reduce the fracture toughness of nanocomposites. The decrease could be due to changes in the morphologies of the epoxy nanocomposites as well as the interfacial debonding between the organoclay and the surrounding epoxy.