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Spherical indentation testing of poroelastic relaxations in thin hydrogel layers



Edwin Chan, Yuhang Hu, Peter M. Johnson, Zhigang Suo, Christopher Stafford


In this work, we present the Poroelastic Relaxation Indentation (PRI) testing approach for quantifying the mechanical and transport properties of thin layers of poly(ethylene glycol) hydrogel materials with thicknesses on the order of 200 m. Specifically, PRI characterizes poroelastic relaxation in hydrogels by indenting the material at fixed depth and tracking the contact area-dependent load relaxation process as a function of time. With the aid of a linear poroelastic theory developed for thin polymer gel layers, we demonstrate that PRI can quantify the shear modulus and diffusion coefficient of water transport within the hydrogel layers. This measurement approach provides a simple methodology to quantify the material properties of thin swollen polymer networks relevant to transport phenomena.
Soft Matter


poroelasticity, diffusion, transport, polymers, hydrogels, modulus, pore size, mechanics


Chan, E. , Hu, Y. , Johnson, P. , Suo, Z. and Stafford, C. (2011), Spherical indentation testing of poroelastic relaxations in thin hydrogel layers, Soft Matter, [online], (Accessed March 2, 2024)
Created December 15, 2011, Updated October 12, 2021