Motion of carbon nanotubes based polymer nanocomposites subjected to multi-directional deformation

Interesting behavior is observed in the electrical resistance across the thickness of glass fibers/epoxy/carbon nanotubes (CNTs) laminate when the laminate is subjected to uniaxial stress along its length. Normally, when a tensile stress is applied along the length of the laminate, Poisson coupling would result in a decrease in the thickness of the laminate. One may expect that this would give rise to smaller electrical resistance across the thickness of the laminate due to the smaller dimension. However, the opposite is observed, ie., an increase in electrical resistance across the thickness. Additional experiments with loading along different directions were imposed on the laminate and electrical resistance was measured. An explanation is provided for this behavior. The results from these simple experiments and the proposed explanation can provide insight into the effect of the motion of the nanostructure on the macro electrical resistance behavior of polymer composite structures containing CNTs when the structure is subjected to multi-directional deformation.