Does Fractal Nanostructure of Filled Rubber Lead to Fractal Deformations? In Situ Measurements of Strain Heterogeneities by AFM

The filler network in filled rubbers exhibits a very disordered structure which is close to a fractal pattern During mechanical solicitation, the inlet action between polymer and the filler network leads to local strong heterogeneous deformation The question is How does the fractal structure of the filler network affect these deformations(9) Direct observation of these microstructures, in particular under an imposed deformation, is difficult, however, A FM phase imaging can fulfill this objective Local deformation of the filler networks has been observed in situ along two loading sequences Fracture in the filler network has been observed, strong deformation heterogeneities have been measured It has been also shown that, from the first loading to the second, the aggregates seem to follow the same path even If the strain heterogeneities increase Finally, along a current line. the heterogeneities of deformation are self-similar until a maximum size is reached. This size has been determined to be approximately 1 mu m, and the return to homogeneity does not occur before 50 mu m