Dramatic changes in the physical properties of composites occur when filler particles form a
percolating network through the composite, particularly when the difference between the
properties of the constitutive phases is large. By use of electric conductivity and dielectric
properties as examples, recent studies on the physical properties of composites near
percolation are reviewed. The effects of geometric factors and intrinsic properties of the
fillers and the matrix, and especially of the interface between fillers and matrix, on electric …