Abstract: A continuum model is presented to study vdW
interaction on buckling analysis of multi-walled walled carbon
nanotube. In previous studies, only the vdW interaction between
adjacent two layers was considered and the vdW interaction between
the other two layers was neglected. The results show that the vdW
interaction cofficients are dependent on the change of interlayer
spacing and the radii of tubes. With increase of radii the vdW
coefficients approach a constant value. The numerical results show
that the effect of vdW interaction on the critical strain for a doublewalled
CNT is negligible when the radius is large enough for the
both the cases of before and after buckling.
Abstract: In this paper, the effect of modified clay on the
mechanical efficiency of epoxy resin is examined. Studies by X ray
diffraction and microscopic transient electron method show that
modified clay distribution in polymer area is intercalated kind.
Examination the results of mechanical tests shows that existence of
modified clay in epoxy area increases pressure yield strength, tension
module and nano composite fracture toughness in relate of pure
epoxy. By microscopic examinations it is recognized too that the
action of toughness growth of this kind of nano composite is due to
crack deflection, formation of new surfaces and fracture of clay piles.