Equivalent continuum models of carbon nanotube reinforced polypropylene composites

Carbon nanotubes (CNTs), as a reinforcing material, are extensively used in nanocomposites for their high stiffness and high strength. To analyze the mechanical properties of CNT reinforced polymer composites, continuum mechanics combined with finite elements methods (FEMs) is a very effective tool. However, adopting different numerical models will directly affect the computing efficiency. In this work, solid element, shell element and 3-D truss element are separately used to simulate single wall carbon nanotube (SWCNT). In addition, the effects of CNT aspect ratio on the mechanical properties of CNT reinforced polypropylene composites are investigated. As a first approximation, the polypropylene matrix material is assumed to be a linear elastic or an elastic–plastic material, while CNT is assumed to be a linear elastic material. A series of direct tensile numerical tests were carried out to get the elastic modulus of SWCNT/polypropylene composites and the transverse deformations of the composites are determined for the range of conditions tested.