Application of two phase model to linear viscoelasticity of reinforced rubbers

A two phase model proposed for accounting for linear viscoelasticity of polymer nanocomposite melts [14] is applied to rubbers filled with nanoclay and conventional fillers (carbon black and silica) to probe mechanisms of the fluid- and the solid-like behaviors beyond the terminal flow region. This model shows strong applicability in linear rheology beyond terminal region for a variation of filled rubbers. Characteristic moduli of the “filler phase” from different filled rubbers could collapse onto a master curve, which reveals a jamming transition with increasing filler concentration across the percolation threshold. The strain amplification effect and reduced characteristic moduli of the “filler phase” are discussed within the framework of the cluster–cluster aggregation model.