Analytical solution of swell-induced surface instability for graded hydrogel layers
To obtain a theoretical solution for the critical condition of swell-induced surface instability,a graded hydrogel layer on a rigid substrate is divided into n fictitious sub-layers.By considering the boundary condition and interface continuity,a governing equation for surface instability is established.Hydrogel layers with the crosslink density varying in the thickness direction are examined in details.The results show that both the critical condition and the instability mode relate to the variation of the material properties.For a soft-on-hard graded layer,the onset of surface instability is determined by a short-wave mode with a limiting short wavelength.In contrast,for a hard-on-soft graded layer,a long-wave mode with a finite wavelength emerges as the critical mode at the onset of surface instability.The critical swelling ratio of the long-wave mode for hard-on-soft graded layers is considerably lower than that of the short-wave limit for soft-on-hard ones with the same shape factor.In addition,we found that both the critical swelling ratio and the characteristic wavelength depend on the gradient profile of material properties.
Hydrogel Surface instability Graded layer
Zhigen Wu Rui Huang Yihua Liu Hao Li
School of Civil Engineering,Hefei University of Technology,Hefei,Anhui 230009,China Department of Aerospace Engineering and Engineering Mechanics,University of Texas,Austin,TX 78712,US
国际会议
北京
英文
1-9
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）