Electrical breakdown in soft elastomers: Stiffness dependence in un-pre-stretched elastomers

The relation between electrical breakdown and mechanical properties in soft polymeric materials is of particular interest for multiple applications, such as smart and flexible materials. In the literature, this relation is commonly investigated by variation of temperature, which indirectly causes a change in mechanical properties, but it also affects other factors that may influence the electrical breakdown, such as conductivity. Here, we present experiments that are performed at a constant temperature, on blends of chemically identical tri-block thermoplastic elastomers with different stiffnesses. Stress-strain measurements proved that continuous variation in mechanical properties could be obtained, here a range of 94-316 kPa was found. Breakdown measurements found that the breakdown field increases with Youngs modulus. The results were compared to several theories in literature, however, only the recently proposed theory of [5] was found to explain the observations adequately.