Effective elastic moduli of polymer-layered silicate nanocomposites

Polymer-layered silicate (PLS) nanocomposites exhibit some mechanical prope rties that are much better than conventional polymer filled composites. A r elatively low content of layered silicate yields a significant enhancement of material performance. After the volume fraction of clay reaches a relati vely low "critical value"; however, further increasing does not show a grea ter stiffening effect. This phenomenon is contrary to previous micromechani cal predictions and Is not understood well. Based on the analysis on the mi crostructures of PLS nanocomposites, the present note provides an insight i nto the physical micromechanisms of the above unexpected phenomenon. The Mo ri-Tanaka scheme and a numerical method are employed to estimate the effect ive elastic moduli of such a composite.