Analysis of Stress Softening Effects and Crack Properties for Polymer Network-Based Soft Materials under Biaxial Stretching

Abstract

This review describes our recent findings on stress-softening, known as the Mullins effect, and fracture behavior in polymer network-based soft materials under biaxial deformation. This study highlights contrasting energy dissipation mechanisms and anisotropic damage characteristics in filler-reinforced elastomers and double network hydrogels, attributing these differences to the distinct origins of internal damage in these materials. We also investigate crack properties, including strain energy release rates and local crack-tip strain fields, under various types of applied deformation. Additionally, we focus on the dynamics of crack propagation, particularly for the transition between subsonic and super-shear speeds and reveal the significant differences in crack-tip properties between these speed regimes. These findings offer valuable insights into the internal damage mechanisms and fracture behavior in soft materials induced by diverse deformations, enhancing the understanding necessary for material design and application.