Frequency-dependent viscoelastic behavior of randomly-distributed-CNT/epoxy nanocomposites using a combined finite element-micromechanics method

A novel approach was developed to predict the frequency-dependent viscoelastic behavior of polymeric nanocomposites by having that of the neat polymer. This approach is a combination of the finite element and micromechanics methods. First, the viscoelastic properties, namely the storage and loss moduli, of an RVE of nanocomposites containing one carbon nanotube (CNT) embedded in a polymer using a finite element method were modeled. The matrix was considered as a continuum phase and each covalent bond of CNT was simulated by an equivalent structural beam. Nonlinear springs were used as van der Waals bonds in the interphase region of CNT and polymer and then the model was subjected to a harmonic load. A micromechanics approach was used to consider the random distribution of CNTs in the polymer. The results obtained from the proposed approach were found to be in good agreement with the results of the micromechanical method which is adjusted for viscoelasticity

Keywords:

Nanocomposites , Carbon nanotube , Viscoelastic properties , FEM , Micromechanics