Ion-Triggered Reconfigurable Hydrogel with Salt-Enhanced Mechanical and Swelling Properties via Network Topological Adaptation

Ion-Triggered Reconfigurable Hydrogel with Salt-Enhanced Mechanical and Swelling Properties via Network Topological Adaptation | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Ion-Triggered Reconfigurable Hydrogel with Salt-Enhanced Mechanical and Swelling Properties via Network Topological Adaptation Liyuan Zhang, Lingling Ren, Guoxuan Ma, Zheng Wang, Shuang Liu, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8077317/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Hydrogels typically deteriorate in high salinity due to electrostatic screening and solvent-quality loss. Here, we report a double network hydrogel, composed of poly(AMPS)(2-acrylamido-2-methylpropane sulfonic acid) and zwitterionic AM-SBVI (acrylamide-sulfobetaine vinylimidazole) that strengthens while swelling in brine. Upon salt exposure, the network undergoes ion-triggered topological reconfiguration, the intrachain zwitterionic loops open and re-form as inter-network SBVI + -AMPS − bridges, which yields a higher effective bridge density v e , at lower polymer fraction(Φ). The hydrogel demonstrates a 3.4-fold increase in tensile strength and a 2.1-fold enhancement in equilibrium swelling ratio in 200 g/L NaCl compared to deionized water. Small-angle X-ray scattering (SAXS) and X-ray photoelectron spectroscopy (XPS) confirm the ion-mediated decoupling of crosslinking domains and redistribution of charge density. Moreover, simulation calculation suggests a more strong interaction between SBVI and AMPS under high salinity water. Coreflooding experiment demonstrates robust injectability and flow-resistance characteristics under high salinity porous rock. A deep analysis concerts swelling/rheology into three descriptors, v ₑ, χ (Flory-Rehner inversion), and f loop (loop fraction from bridge capacity). We find that salt contents raise and depress f loop toward zero. This, the elastic cost term, F el increases but is compensated by F assoc (stabilization from loop to bridge), while F diss from Donnan partioning is small. F mix that related to χ shifts quite small indicated a strong interaction between the hydrogel with brine. This quantitative mechanism explains the simultaneous gains in swelling and modulus and provides rational design rules to engineer salt-adaptive hydrogels for subsurface and biointerfaces. Physical sciences/Materials science/Soft materials/Gels and hydrogels Physical sciences/Materials science/Soft materials/Organic molecules in materials science salt reinforcement hydrogel zwitterionic complexation topological reconfiguration high salinity double network Full Text Additional Declarations There is NO Competing Interest. Supplementary Files supportinginformation.docx Supporting Information--Ionic Complex Engineered Topologically Reconfigurable Salt-Resistant Hydrogels with Simultaneously Enhanced Swelling and Mechanical Properties Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8077317","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":550068114,"identity":"3396b623-2068-4cd8-b0cb-239326e46eee","order_by":0,"name":"Liyuan 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Here, we report a double network hydrogel, composed of poly(AMPS)(2-acrylamido-2-methylpropane sulfonic acid) and zwitterionic AM-SBVI (acrylamide-sulfobetaine vinylimidazole) that strengthens while swelling in brine. Upon salt exposure, the network undergoes ion-triggered topological reconfiguration, the intrachain zwitterionic loops open and re-form as inter-network SBVI\u003csup\u003e+\u003c/sup\u003e-AMPS\u003csup\u003e\u0026minus;\u003c/sup\u003e bridges, which yields a higher effective bridge density \u003cem\u003ev\u003c/em\u003e\u003csub\u003ee\u003c/sub\u003e, at lower polymer fraction(Φ). The hydrogel demonstrates a 3.4-fold increase in tensile strength and a 2.1-fold enhancement in equilibrium swelling ratio in 200 g/L NaCl compared to deionized water. Small-angle X-ray scattering (SAXS) and X-ray photoelectron spectroscopy (XPS) confirm the ion-mediated decoupling of crosslinking domains and redistribution of charge density. Moreover, simulation calculation suggests a more strong interaction between SBVI and AMPS under high salinity water. Coreflooding experiment demonstrates robust injectability and flow-resistance characteristics under high salinity porous rock. A deep analysis concerts swelling/rheology into three descriptors, \u003cem\u003ev\u003c/em\u003eₑ, χ (Flory-Rehner inversion), and f\u003csub\u003eloop\u003c/sub\u003e (loop fraction from bridge capacity). We find that salt contents raise and depress f\u003csub\u003eloop\u003c/sub\u003e toward zero. This, the elastic cost term, F\u003csub\u003eel\u003c/sub\u003e increases but is compensated by F\u003csub\u003eassoc\u003c/sub\u003e(stabilization from loop to bridge), while F\u003csub\u003ediss\u003c/sub\u003e from Donnan partioning is small. F\u003csub\u003emix\u003c/sub\u003e that related to χ shifts quite small indicated a strong interaction between the hydrogel with brine. This quantitative mechanism explains the simultaneous gains in swelling and modulus and provides rational design rules to engineer salt-adaptive hydrogels for subsurface and biointerfaces.\u003c/p\u003e","manuscriptTitle":"Ion-Triggered Reconfigurable Hydrogel with Salt-Enhanced Mechanical and Swelling Properties via Network Topological Adaptation","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-28 05:38:11","doi":"10.21203/rs.3.rs-8077317/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"93637db1-aa82-4399-9ebe-44c5e1757da7","owner":[],"postedDate":"November 28th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":58524950,"name":"Physical sciences/Materials science/Soft materials/Gels and hydrogels"},{"id":58524951,"name":"Physical sciences/Materials science/Soft materials/Organic molecules in materials science"}],"tags":[],"updatedAt":"2026-05-13T02:05:28+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-28 05:38:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8077317","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8077317","identity":"rs-8077317","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}