Open AccessMechanical characterization of PVA hydrogels’ rate-dependent response using multi-axial loading
Author(s) -
Wanis Nafo,
Adil Al-Mayah
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0233021
Subject(s) - viscoelasticity , materials science , self healing hydrogels , indentation , composite material , ultimate tensile strength , characterization (materials science) , natural rubber , finite element method , tensile testing , material properties , compression (physics) , structural engineering , nanotechnology , polymer chemistry , engineering
The time-dependent properties of rubber-like synthesized and biological materials are crucial for their applications. Currently, this behavior is mainly measured using axial tensile test, compression test, or indentation. Limited studies performed on using multi-axial loading measurements of time-dependent material behavior exist in the literature. Therefore, the aim of this study is to investigate the viscoelastic response of rubber-like materials under multi-axial loading using cavity expansion and relaxation tests. The tests were performed on PVA hydrogel specimens. Three hyperelasitc models and one term Prony series were used to characterize the viscoelastic response of the hydrogels. Finite element (FE) simulations were performed to verify the validity of the calibrated material coefficients by reproducing the experimental results. The excellent agreement between the experimental, analytical and numerical data proves the capability of the cavity expansion technique to measure the time-dependent behavior of viscoelastic materials.