ABSTRACT
ABSTRACT: Whereas unfilled elastomers show nearly ideally hyperelastic behavior, the differences in the stress response by adding filler are connected to the interaction between the polymer and the filler. Filling of the polymer leads not only to a reinforcement but increases also the hysteresis and stress-softening. By evaluating the displacements of an airbrushed pattern on notched Pure-Shear samples with an ARAMIS system, the displacement fields around the crack tip are obtained. Using a physically motivated model of stress softening and hysteresis of filled rubber the energy density and stress distribution can be calculated. We are able to determine the J-Integral J for closed contours around the crack tip. For purely elastic materials the value of J is path-independent but due to energy dissipation the J-Integral depends on the integration path. By variation of the strain amplitude and the integration path the impact of stress softening on the J-Integral is evaluated.
