Polymer Engineering and Science, Vol.46, No.11, 1625-1634, 2006
On surface deformation of melt-intercalated polyethylene-clay nanocomposites during scratching
Electron microscopy has been used to examine the mechanically-induced surface damage introduced during scratching of polyethylene(PE)- clay nanocomposites. The determining role of clay in reducing the susceptibility to surface deformation is predicted from the characteristics of surface morphology and the scratch deformation parameters. The reinforcement of PE with nanoclay reduces the susceptibility to scratch damage and stress whitening. Microcracks and surface deformation features namely wrinkles/ridges are the primary source of light scattering resulting in stress whitening. The scratch deformation behavior is discussed in terms of tensile modulus, percentage crystallinity, elastic recovery, and scratch hardness. Scratch hardness is a relevant parameter that can be appropriately used to determine resistance to scratch deformation.