Hydrogels hold promise in agriculture as reservoirs of water in dry soil, potentially alleviating the burden of irrigation. However, confinement in soil can markedly reduce the ability of hydrogels to absorb water and swell, limiting their widespread adoption. Unfortunately, the underlying reason remains unknown. By directly visualizing the swelling of hydrogels confined in three-dimensional granular media, we demonstrate that the extent of hydrogel swelling is determined by the competition between the force exerted by the hydrogel due to osmotic swelling and the confining force transmitted by the surrounding grains. Furthermore, the medium can itself be restructured by hydrogel swelling, as set by the balance between the osmotic swelling force, the confining force, and intergrain friction. Together, our results provide quantitative principles to predict how hydrogels behave in confinement, potentially improving their use in agriculture as well as informing other applications such as oil recovery, construction, mechanobiology, and filtration.
Biocompatible Microscale DNA Hydrogels with Programmable Swelling and Sequence-Specific Dissolution
Johns Hopkins University（约翰斯·霍普金斯大学）；Johns Hopkins University School of Medicine（约翰斯·霍普金斯大学医学院）；The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Hospital（约翰斯·霍普金斯医院西德尼·基梅尔综合癌症中心）
Non-uniform swelling of polyelectrolyte hydrogels: effects of charge regulation
Wenzhou University（温州大学）；Zhejiang Key Laboratory of Soft Matter Biomedical Materials, Wenzhou Institute, University of Chinese Academy of Sciences（中国科学院大学温州研究院软物质生物医用材料浙江省重点实验室）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；School of Physics and Astronomy, & Center for Physics and Chemistry of Living Systems, Tel Aviv University（特拉维夫大学物理与天文学学院及生命系统物理化学中心）；School of Sino-German Engineering, Shanghai Technical Institute of Electronics and Information（上海电子与信息工程技术学院中德工程学院）
Reciprocal swimming in viscoelastic granular hydrogels
Friedrich-Alexander-Universität Erlangen-Nürnberg（埃尔朗根-纽伦堡弗里德里希·亚历山大大学）；University of Michigan（密歇根大学）；Otto von Guericke University Magdeburg（马格德堡奥托·冯·格里克大学）；Brandenburg University of Applied Sciences（勃兰登堡应用科技大学）
Pressure sensitivity in non-local flow behaviour of dense hydrogel particle suspensions
Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam（阿姆斯特丹大学范德瓦耳斯-泽曼研究所物理学院）；Physical Chemistry and Soft Matter, Wageningen University & Research（瓦赫宁根大学与研究物理化学与软物质系）；Institute of Process and Particle Engineering, Graz University of Technology（格拉茨工业大学工艺与颗粒工程研究所）；Department of Mechanical Engineering, Indian Institute of Technology Bombay（印度孟买理工学院机械工程系）；Institute of Physics, Otto von Guericke University Magdeburg（马格德堡奥托·冯·格里克大学物理研究所）；School of Engineering, Brown University（布朗大学工程学院）
