STRUCTURE AND PROPERTIES OF FRACTAL FILLE R NETWORKS IN RUBBER

The effect of filler networking on mechanical and electrical propertie s of elastomers is discussed on the basis of two models: percolation t heory and kinetical cluster-cluster-aggregation. Both models imply fra ctal characteristics for the filler network, but differ in the predict ed structure of the fractal unit cells and the dependence of the cell size xi on filler concentration. The mechanical and electrical propert ies of the two network models are compared to the properties of carbon black filled rubbers. It is shown that the scaling properties of the small strain modulus of N330/butyl-vulcanisates as measured by Payne a gree with the predictions of the kinetical model.