Numerical simulation of the tensile modulus of nanoclay-filled polymer composites

A numerical simulation model that incorporates three phases, polymer matrix, interlayer, and clay platelet, was developed to predict the tensile modulus of nanoclay-filled polymer composites. The interlayer was introduced to account for the fact that the mechanical properties of the polymer near the clay surface are different from those of the polymer matrix. The effects of the properties of interlayers, the structure of clay clusters, and platelet distributions upon the modulus of elasticity of the nanocomposites, were studied. The simulation results show that a decrease in the interlayer modulus, as well as an increase in the interlayer thickness, would decrease the modulus of the nanocomposites. Furthermore, it was found that the maximum strain, located in the interlayer near the end of the clay platelet, increases significantly with decreasing interlayer modulus. The effects of the distribution of clay platelets upon composite modulus were interpreted in terms of two parameters, platelet overlap length, and the lateral distance between platelets. Comparison of simulation results with experimental data from the literature has confirmed the reliability of the numerical simulation method used in the present study. (C) 2004 Wiley Periodicals, Inc.