Effects of crosslinking point functionality and network entanglement on buckling instability of hydrogel films

doi:10.3969/j.issn.1000-1565.2020.06.005

Abstract

Abstract: The research on the buckling instability of hydrogel films has been the focus of the application of hydrogel films. In this paper, effects of topological network structure of hydrogels and network entanglement effect of polymer network that constitutes hydrogels on large coupling deformation of hydrogels are taken into account. A free energy equation combining the slip-link model proposed by Edwards-Vilgis with Flory-Huggins theory is introduced to demonstrate the real influence of polymer network on large deformation of hydrogels in the chemo-mechanical coupling field. The critical stress and wavelength of unidirectional nonlinear buckling of two-dimensional hydrogel films were solved by analytical method, and the influence of the microstructure of polymer network that constitutes hydrogels on the buckling of hydrogel films under different external solution environment conditions was discussed.- DOI:10.3969/j.issn.1000-1565.2020.06.005交联点官能度和网络缠结效应对凝胶薄膜屈曲失稳的影响李涛,杨庆生(北京工业大学机械工程与应用电子技术学院,北京 100124)摘要:对于响应型水凝胶薄膜屈曲失稳行为的研究一直是水凝胶薄膜应用中的重点.本文考虑水凝胶拓扑网络结构以及构成水凝胶的高分子网络缠结效应凝胶耦合大变形中的影响,引入了一种将Edwards-Vilgis的slip-link模型与Flory-Huggins理论相结合的自由能方程,旨在还原水凝胶在化学-力学耦合场作用下发生大变形时真实高分子网络的作用.通过解析方法求解了二维水凝胶薄膜单向非线性屈曲的临界应力和波长,探讨了外部溶液环境变化时,构成水凝胶的高分子网络微结构对凝胶薄膜屈曲的影响.结果表明:水凝胶的微结构参数在较小数值变化时对水凝胶增量模量以及凝胶薄膜屈曲的临界应力和波长有显著影响,当微结构参数不断变大这种影响逐渐减弱.关键词:水凝胶薄膜;屈曲;化学-力学耦合;解析解中图分类号:O345 文献标志码:A 文章编号:1000-1565(2020)06-0591-06Effects of crosslinking point functionality and network entanglement on buckling instability of hydrogel filmsLI Tao, YANG Qingsheng(College of Engineering Mechanics, Beijing University of Technology, Beijing 100124, China)Abstract: The research on the buckling instability of hydrogel films has been the focus of the application of hydrogel films. In this paper, effects of topological network structure of hydrogels and network entanglement effect of polymer network that constitutes hydrogels on large coupling deformation of hydrogels are taken into account. A free energy equation combining the slip-link model proposed by Edwards-Vilgis with Flory-Huggins theory is introduced to demonstrate the real influence of polymer network on large deformation of hydrogels in the chemo-mechanical coupling field. The critical stress and wavelength of unidirectional nonlinear buckling of two-dimensional hydrogel films were solved by analytical method, and the influence of the microstructure of polymer network that constitutes hydrogels on the buckling of hydrogel films under different external solution environment conditions was discussed.- 收稿日期:2020-03-02 基金项目:国家自然科学基金资助项目(11572109;11632005);河北省自然科学基金资助项目(11572109);河北省高校技术研究项目(ZD2017006) 第一作者:李涛(1989—),男,河北保定人,北京工业大学在读博士,主要从事智能软材料多物理场耦合行为研究. E-mail:1047427142@emails.bjut.edu.cn 通信作者:杨庆生(1962—),男,河北故城人,北京工业大学教授,博士,主要从事智能软材料多物理场耦合行为研究.E-mail:qsyang@bjut.edu.cn第6期李涛等:交联点官能度和网络缠结效应对凝胶薄膜屈曲失稳的影响The results show that the microstructure parameters of hydrogels have a significant influence on the incremental modulus of hydrogels and the critical stress and wavelength of the buckling of hydrogel firms when the value change of parameter is small.

Key words: hydrogel film, buckling, chemo-mechanical coupling, analytical solution

CLC Number:

O345

LI Tao, YANG Qingsheng. Effects of crosslinking point functionality and network entanglement on buckling instability of hydrogel films[J]. Journal of Hebei University(Natural Science Edition), 2020, 40(6): 591-596.

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