Fractal geometry change induced by compression densification

Texture change induced by an isostatic compression of low density aerogels exhibiting fractal geometry has been investigated. Fractal features are analyzed from small angle X-ray scattering experiments. It was found that at the onset of densification a decrease in the correlation length occurs while the fractal dimension increases a little. Isostatic compression leads to cluster interpenetration. This provoked solid arm entanglement modifies the fractal range of cluster. For higher pressures correlation length does not change indicating that the cluster size is constant. Further densification has been related to the collapse of pores located between clusters. (C) 1998 Elsevier Science B.V. All rights reserved.