Numerical evaluation of effective elastic properties of CNT-reinforced polymers for interphase effects

This paper presents the stiffening effect of carbon nanotubes dispersed in polymer composites using micromechanics models and finite element analysis. The effective elastic modulus of carbon nanotube (CNT)-reinforced composites is predicted by assuming that all the CNTs are either aligned or randomly oriented in the polymer matrix. An extended three-phase rule of mixture is implemented to analyze the effect of interphase properties on the effective elastic modulus. Homogenized representative volume element with multiple CNTs embedded inside the matrix with an interface layer is employed. The analysis is performed using a 3D finite element model of the representative volume element. Effects of interface stiffness, its thickness and dispersion of CNTs within the polymer matrix are studied. Results reveal the extent these factors influencing the elastic modulus of the composite.