Multiscale Modeling of Polymer-Clay Nanocomposites: Interphase and Homogenization Methods

摘要

A 3D periodic Finite Element (FE) model with the concept of effective particles hasrnbeen developed in order to validate the commonly used homogenizations models forrnPolymer Clay Nanocomposites (PCNs). The interfacial interaction between clay andrnpolymer at the molecular scale is incorporated in the model by a third phasern(interphase). Two steps of the homogenization are used to obtain the properties ofrneffective particles and the properties of the composite. The effective particle inrnexfoliated nanocomposites, homogenized at the first step, contains clay as well asrnthe interphase. The effect of varying the volume fraction of the effective particle asrna function of effective thickness of the modified polymer as well as the volumernfraction of nano-clay is studied with different models of homogenization (Mori-rnTanaka, Self-Consistent and Lielens) in the second stage of homogenization. Tornfind the appropriate model at differenets volume fractions, the predictions of the 3DrnFE method has been used. It is observed that the Lielens model is the most precisernmodel for incorporating the interphase which has commonly reported properties.rnHowever, the parametric studies show that by changing the properties of therninterphase, the most accurate method may be other than Lielens.