Rate-dependent failure mechanism of elastomers

Elastomers display a mechanical behavior that is, both in the elastic as well as at the incipient failure, quite different from that of traditional materials. Their mechanical characteristics makes them attractive to a myriad of applications ranging from rubber, optical lenses to tissue engineering scaffolds. Their study is therefore fundamental for understanding and controlling their mechanical response, especially when it involves large deformation, viscous effects and damage nucleation around defects. In the present paper we consider the mechanical response up to final failure, of pre-cracked silicone sheets under different strain rates. A simple statistically-based theoretical model, combined with a failure criterion, is formulated to describe the observed complex mechanical response. The model is further implemented in a finite element model to provide comparison of the damage nucleation predicted by the model and those obtained from experimental tests.