{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T22:23:31Z","timestamp":1785363811626,"version":"3.55.0"},"reference-count":58,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,9]],"date-time":"2023-02-09T00:00:00Z","timestamp":1675900800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["32173026"],"award-info":[{"award-number":["32173026"]}]},{"name":"National Natural Science Foundation of China","award":["52103019"],"award-info":[{"award-number":["52103019"]}]},{"name":"National Natural Science Foundation of China","award":["2021SX-TD001"],"award-info":[{"award-number":["2021SX-TD001"]}]},{"name":"National Natural Science Foundation of China","award":["2021SX-TD010"],"award-info":[{"award-number":["2021SX-TD010"]}]},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering","award":["32173026"],"award-info":[{"award-number":["32173026"]}]},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering","award":["52103019"],"award-info":[{"award-number":["52103019"]}]},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering","award":["2021SX-TD001"],"award-info":[{"award-number":["2021SX-TD001"]}]},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering","award":["2021SX-TD010"],"award-info":[{"award-number":["2021SX-TD010"]}]},{"name":"2021 Major Science and Technology Program of Taiyuan","award":["32173026"],"award-info":[{"award-number":["32173026"]}]},{"name":"2021 Major Science and Technology Program of Taiyuan","award":["52103019"],"award-info":[{"award-number":["52103019"]}]},{"name":"2021 Major Science and Technology Program of Taiyuan","award":["2021SX-TD001"],"award-info":[{"award-number":["2021SX-TD001"]}]},{"name":"2021 Major Science and Technology Program of Taiyuan","award":["2021SX-TD010"],"award-info":[{"award-number":["2021SX-TD010"]}]},{"name":"Fund for Shanxi \u201c1331 Project\u201d","award":["32173026"],"award-info":[{"award-number":["32173026"]}]},{"name":"Fund for Shanxi \u201c1331 Project\u201d","award":["52103019"],"award-info":[{"award-number":["52103019"]}]},{"name":"Fund for Shanxi \u201c1331 Project\u201d","award":["2021SX-TD001"],"award-info":[{"award-number":["2021SX-TD001"]}]},{"name":"Fund for Shanxi \u201c1331 Project\u201d","award":["2021SX-TD010"],"award-info":[{"award-number":["2021SX-TD010"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Biological soft tissues are intrinsically viscoelastic materials which play a significant role in affecting the activity of cells. As potential artificial alternatives, double-network (DN) gels, however, are pure elastic and mechanically time independent. The viscoelasticization of DN gels is an urgent challenge in enabling DN gels to be used for advanced development of biomaterial applications. Herein, we demonstrate a simple approach to regulate the viscoelasticity of tough double-network (DN) hydrogels by forming sulfonate\u2013metal coordination. Owing to the dynamic nature of the coordination bonds, the resultant hydrogels possess highly viscoelastic, mechanical time-dependent, and self-recovery properties. Rheological measurements are performed to investigate the linear dynamic mechanical behavior at small strains. The tensile tests and cyclic tensile tests are also systematically performed to evaluate the rate-dependent large deformation mechanical behaviors and energy dissipation behaviors of various ion-loaded DN hydrogels. It has been revealed based on the systematic analysis that robust strong sulfonate\u2013Zr4+ coordination interactions not only serve as dynamic crosslinks imparting viscoelastic rate-dependent mechanical performances, but also strongly affect the relative strength of the first PAMPS network, thereby increasing the yielding stress \u03c3y and the fracture stress at break \u03c3b and reducing the stretch ratio at break \u03bbb. It is envisioned that the viscoelasticization of DN gels enables versatile applications in the biomedical and engineering fields.<\/jats:p>","DOI":"10.3390\/gels9020145","type":"journal-article","created":{"date-parts":[[2023,2,9]],"date-time":"2023-02-09T02:55:54Z","timestamp":1675911354000},"page":"145","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Metal-Coordinated Dynamics and Viscoelastic Properties of Double-Network Hydrogels"],"prefix":"10.3390","volume":"9","author":[{"given":"Shilei","family":"Zhu","sequence":"first","affiliation":[{"name":"College of Physics, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhe","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fengbo","family":"Zhu","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5023-4487","authenticated-orcid":false,"given":"Yanan","family":"Ye","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9445-1229","authenticated-orcid":false,"given":"Yong","family":"Zheng","sequence":"additional","affiliation":[{"name":"Institute for Chemical Reaction Design and Discovery, Hokkaido University, Sapporo 001-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenwen","family":"Yu","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiang","family":"Zheng","sequence":"additional","affiliation":[{"name":"College of Materials Science & Engineering, Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1023\/B:JMSM.0000026104.30607.c7","article-title":"Evaluation of fracture toughness of cartilage by micropenetration","volume":"15","author":"Simha","year":"2004","journal-title":"J. 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