Multi-axial mechanical properties of hydrogel-based materials upon finite strains: towards the design of tailored vocal-fold composite replicas

In vitro modeling of phonation requires materials able to mimic the vibro-mechanical features of vocal-fold tissues: ability to (i) endure large deformations under physiological multiaxial loadings and strain rates], (ii) adapt their vibromechanical behavior to external loadings and environmental changes. Among relevant candidates, hydrogels are attractive materials due to their tissue-like water content. However, the mechanical characterization of hydrogels is often limited to single monotonic loadings, mainly in compression, or to standard DMA analyses. These configurations are far from those endured by the tissue in vivo. Here, we manufactured hydrogels with tunable mechanical properties that we characterized under realistic, finite strain, cyclic tension, compression and shear loadings.