Micro-mechanical modeling of the stress softening in double-network hydrogels

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:164

Article

Morovati, Vahid¹  Dargazany, Roozbeh¹ 

[1] Michigan State Univ, Dept Civil & Environm Engn, E Lansing, MI 48864 USA

关键词: Micro-structures;    Anisotropic material;    Constitutive behavior;    Double network hydrogels;    Mullins effect;   

DOI  :  10.1016/j.ijsolstr.2019.01.002

来源: Elsevier

【 摘 要 】

While single network hydrogels show limited extensibility and low strength, double-network (DN) hydrogels benefit from significantly high stretch-ability and toughness due to their reinforcing mechanism of combining two soft and brittle networks. Here, a micro-mechanical model is developed to characterize the constitutive behavior of DN hydrogels in quasi-static large deformation. In particular, we focused on describing the permanent damage in DN gels under large deformations. Irreversible chain detachment and decomposition of the first network are explored as the underlying reasons for the nonlinear inelastic phenomenon. The proposed model enables us to describe the damage and the way it influences the micro-structure of the gel. The model is validated with uni-axial loading and unloading experiments of DN gels. The proposed model contains a few material constants and shows a good agreement with cyclic uni-axial test data. (C) 2019 Published by Elsevier Ltd.

【 授权许可】

Free