查看文章

Viscoelasticity is an essential mechanical property of soft materials. Many constitutive models have been proposed to capture this mechanical behavior, but few physically based models were developed due to the challenge to incorporate the micro-mechanisms of viscoelasticity into the formulation. In a previous paper, we proposed a constitutive model to characterize the hyperelastic response under different deformation states with only three parameters (Xiang et al., 2018). Based on the above work and the tube theory of polymer dynamics, we develop herein a physically based viscoelastic constitutive model in this paper. We start from a new microscopic picture at the molecular chain scale, and decompose the stress into a hyperelastic part which comes from the elastic ground network (crosslinked network and entanglement network), and a viscous part which is originated from free chains. Utilizing the same …