Softening of the Hertz indentation contact in nematic elastomers

Polydomain liquid crystalline (nematic) elastomers have highly unusual mechanical properties, dominated by the dramatically nonlinear stress–strain response that reflects stress-induced evolution of domain patterns. Here, we study classical Hertz indentation problem in such a material. Experimentally, find polydomain nematic display smaller exponent than 3/2 load vs. depth response. This is puzzling: asymptotically softer requires larger at small loads. We resolve this theory where three regimes are identified — an initial elastic regime for shallow obscured experiment, intermediate local pattern leads to scaling agreement with experiments, and final stiffening completion returns elastic. three-regime structure universal, but not. discuss how our work supports new mechanism enhanced adhesion pressure-sensitive elastomers.