STRUCTURAL PROPERTIES OF COMPOSITE ELASTOMERIC MEMBRANES USING SMALL-ANGLE NEUTRON SCATTERING

The morphology of elastomeric membranes based on silicone rubber, at various concentrations of the catalyst (C) is determined by small-angle neutron scattering (SANS) technique. Nearly all membranes display a hierarchical organization of crystallites in which ramified mesoscale mass fractals are composed of either mass or surface-like nano fractals. We use the Beaucae model in order to extract information about the radius of gyration of the clusters and about their fractal dimensions. We show that the fractal dimension of the mesoscale fractal is fixed at 2.68 and is independent with the addition of C. However, the nanoscale fractals are characterized by a transition from mass to surface-like fractals at high values of C concentrations.