{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T11:42:42Z","timestamp":1789731762519,"version":"4.0.1"},"reference-count":48,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,11,24]],"date-time":"2025-11-24T00:00:00Z","timestamp":1763942400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and Higher Education of the Republic of Kazakhstan","award":["AP22788736"],"award-info":[{"award-number":["AP22788736"]}]},{"name":"Ministry of Science and Higher Education of the Republic of Kazakhstan","award":["BR27199103"],"award-info":[{"award-number":["BR27199103"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Polyampholyte hydrogels are promising for load-bearing biomedical applications, but the link between composition and compression behavior remains unclear. In this study, we investigate how initial monomer concentration and a neutral comonomer influence swelling and mechanical properties in AMPS\u2013APTAC networks. Terpolymeric AMPS\u2013APTAC\u2013DMAAm hydrogels were prepared with monomer concentrations from 1 to 2 M, MBAAm levels from 1 to 5 mol%, and DMAAm fractions from 0 to 0.16. Swelling was measured in water. Unconfined compression tests at 3 mm\u00b7min\u22121 provided stress\u2013strain curves, Young\u2019s modulus (E), fracture stress (\u03c3f), fracture strain (\u03b5f), and toughness (W) up to 99% strain. Increasing the monomer concentration produced denser networks, lower swelling, and higher stiffness. For C2M1, E reached 35.4 kPa, \u03c3f reached 0.8 MPa, \u03b5f was 82%, and W was 65.6 kJ\u00b7m\u22123. Adding DMAAm strengthened the gels through reversible associative interactions. At z = 0.06, \u03c3f increased to 4.28 MPa and W to 196.0 kJ\u00b7m\u22123. At z = 0.16, E increased to 103.0 kPa, while \u03c3f was 2.34 MPa and W was 191.6 kJ\u00b7m\u22123. Swelling decreased when monomer or crosslinker content increased. These results show that monomer concentration and DMAAm-mediated associations act as separate design variables that can be tuned to optimize stiffness, strength, and toughness in AMPS\u2013APTAC polyampholyte hydrogels.<\/jats:p>","DOI":"10.3390\/gels11120941","type":"journal-article","created":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T17:31:34Z","timestamp":1764091894000},"page":"941","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Unveiling the Compression Mechanical Properties of AMPS\u2013APTAC\u2013DMAAm Terpolymeric Hydrogels"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0708-1232","authenticated-orcid":false,"given":"Madina","family":"Mussalimova","sequence":"first","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"},{"name":"Research Institute of Advanced Materials, Almaty 040000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nargiz","family":"Gizatullina","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"},{"name":"Research Institute of Advanced Materials, Almaty 040000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gaukhargul","family":"Yelemessova","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"},{"name":"Research Institute of Advanced Materials, Almaty 040000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anel","family":"Taubatyrova","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"},{"name":"Research Institute of Advanced Materials, Almaty 040000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gulzat","family":"Aitkaliyeva","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2551-0723","authenticated-orcid":false,"given":"Zhanserik","family":"Shynykul","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"},{"name":"Research Institute of Advanced Materials, Almaty 040000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6643-6788","authenticated-orcid":false,"given":"Esra","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Aquatic Biotechnology, Faculty of Aquatic Sciences, Istanbul University, 34134 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0381-6665","authenticated-orcid":false,"given":"Gaukhar","family":"Toleutay","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biochemical Engineering, Geology and Oil-Gas Business Institute Named After K. Turyssov, Satbayev University, Almaty 050043, Kazakhstan"},{"name":"Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"814","DOI":"10.1002\/macp.200300174","article-title":"Swelling, Elasticity and Spatial Inhomogeneity of Poly(N,N-dimethylacrylamide) Hydrogels Formed at Various Polymer Concentrations","volume":"205","author":"Gundogan","year":"2004","journal-title":"Macromol. Chem. Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2","DOI":"10.3390\/gels3010003","article-title":"Responsive Hydrogels from Associative Block Copolymers: Physical Gelling through Polyion Complexation","volume":"3","author":"Papadakis","year":"2017","journal-title":"Gels"},{"key":"ref_3","first-page":"53","article-title":"Swelling Behavior Study of Physically Cross-Linked Gelatin Hydrogels","volume":"20","author":"Qiao","year":"2012","journal-title":"Polym. Polym. Compos."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.eurpolymj.2019.01.052","article-title":"Structure\u2013Property Relationships of Novel Phosphonate-Functionalized Networks and Gels of Poly(\u03b2-Amino Esters)","volume":"113","author":"Altuncu","year":"2019","journal-title":"Eur. Polym. J."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"358","DOI":"10.1246\/cl.121263","article-title":"Synthesis of Carboxymethyl Poly(1-vinylimidazole) as a Polyampholyte for Biocompatibility","volume":"42","author":"Asayama","year":"2013","journal-title":"Chem. Lett."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3292","DOI":"10.1021\/acs.langmuir.0c00114","article-title":"Enhanced Biocompatibility of Polyampholyte Hydrogels","volume":"36","author":"Haag","year":"2020","journal-title":"Langmuir"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2583","DOI":"10.1039\/b924290b","article-title":"Why Are Double Network Hydrogels So Tough?","volume":"6","author":"Gong","year":"2010","journal-title":"Soft Matter"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1039\/C5MH00127G","article-title":"Extremely Tough Composites from Fabric Reinforced Polyampholyte Hydrogels","volume":"2","author":"King","year":"2015","journal-title":"Mater. Horiz."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1007\/s00396-020-04605-8","article-title":"Highly Stretchable and Thermally Healable Polyampholyte Hydrogels via Hydrophobic Modification","volume":"298","author":"Toleutay","year":"2020","journal-title":"Colloid Polym. Sci."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1016\/j.jtice.2015.09.011","article-title":"Preparation and Study on the Volume Phase Transition Properties of Novel Carboxymethyl Chitosan Grafted Polyampholyte Superabsorbent Polymers","volume":"59","author":"Chen","year":"2016","journal-title":"J. Taiwan Inst. Chem. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"E131","DOI":"10.1002\/adv.20277","article-title":"Synthesis and Properties of Konjac Glucomannan-Graft-Poly(Acrylic Acid-Co-Trimethylallyl Ammonium Chloride) as a Novel Polyampholytic Superabsorbent","volume":"32","author":"Tian","year":"2013","journal-title":"Adv. Polym. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"13402","DOI":"10.1021\/acs.langmuir.5b03597","article-title":"Characterizing Drug Release from Nonfouling Polyampholyte Hydrogels","volume":"31","author":"Barcellona","year":"2015","journal-title":"Langmuir"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1724","DOI":"10.1021\/acsapm.9b00287","article-title":"One-Step Injectable and Bioreducible Poly(\u03b2-Amino Ester) Hydrogels as Controlled Drug Delivery Platforms","volume":"1","author":"Bingol","year":"2019","journal-title":"ACS Appl. Polym. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Chen, Y.M., and Sun, P.J. (2019). pH-Sensitive Polyampholyte Microgels of Poly(Acrylic Acid-Co-Vinylamine) as Injectable Hydrogel for Controlled Drug Release. Polymers, 11.","DOI":"10.3390\/polym11020285"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1606","DOI":"10.1002\/app.12337","article-title":"Dynamic Swelling Behavior of pH-Sensitive Anionic Hydrogels Used for Protein Delivery","volume":"89","author":"Kim","year":"2003","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"11784","DOI":"10.1021\/acs.jpcb.8b08344","article-title":"Helical Polyampholyte Sequences Have Unique Thermodynamic Properties","volume":"122","author":"Batchelor","year":"2018","journal-title":"J. Phys. Chem. B"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1039\/C8CS00508G","article-title":"An Introduction to Zwitterionic Polymer Behavior and Applications in Solution and at Surfaces","volume":"48","author":"Blackman","year":"2019","journal-title":"Chem. Soc. Rev."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Haag, S.L., and Bernards, M.T. (2017). Polyampholyte Hydrogels in Biomedical Applications. Gels, 3.","DOI":"10.3390\/gels3040041"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"14537","DOI":"10.1021\/acsami.5b02912","article-title":"Synthesis and Biomedical Applications of Poly((Meth)Acrylic Acid) Brushes","volume":"7","author":"Qu","year":"2015","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3112","DOI":"10.1021\/bm4007369","article-title":"Multifunctional Polyampholyte Hydrogels with Fouling Resistance and Protein Conjugation Capacity","volume":"14","author":"Schroeder","year":"2013","journal-title":"Biomacromolecules"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4245","DOI":"10.1021\/acs.macromol.6b00437","article-title":"Self-Healing Behaviors of Tough Polyampholyte Hydrogels","volume":"49","author":"Sun","year":"2016","journal-title":"Macromolecules"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"8833","DOI":"10.1039\/C6SM01833E","article-title":"Stretching-Induced Ion Complexation in Physical Polyampholyte Hydrogels","volume":"12","author":"Cui","year":"2016","journal-title":"Soft Matter"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1800160","DOI":"10.1002\/masy.201800160","article-title":"Quenched Polyampholyte Hydrogels Based on (3-Acrylamidopropyl)Trimethyl Ammonium Chloride and Sodium Salt of 2-Acrylamido-2-Methyl-1-Propanesulfonic Acid","volume":"385","author":"Toleutay","year":"2018","journal-title":"Macromol. Symp."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"35","DOI":"10.31489\/2019Ch4\/35-43","article-title":"Swelling and Mechanical Properties of Quenched Polyampholyte Hydrogels Based on 2-Acrylamido-2-Methyl-1-Propanesulfonic Acid Sodium Salt (AMPS) and (3-Acrylamidopropyl)Trimethylammonium Chloride (APTAC)","volume":"96","author":"Toleutay","year":"2019","journal-title":"Bull. Univ. Karaganda Chem."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"35","DOI":"10.31489\/2019Ch2\/35-44","article-title":"Solution Behavior of Quenched or Strongly Charged Polyampholytes in Aqueous-Salt Solutions","volume":"94","author":"Toleutay","year":"2019","journal-title":"Bull. Univ. Karaganda Chem."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3131","DOI":"10.3390\/polym15143131","article-title":"Equimolar Polyampholyte Hydrogel Synthesis Strategies with Adaptable Properties","volume":"15","author":"Toleutay","year":"2023","journal-title":"Polymers"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2043","DOI":"10.1021\/acsapm.2c02085","article-title":"Mechanically Strong Superabsorbent Terpolymer Hydrogels Based on AMPS via Hydrogen-Bonding Interactions","volume":"5","author":"Sekizkardes","year":"2023","journal-title":"ACS Appl. Polym. Mater."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Antipova, C.G., Krupnin, A.E., Zakirov, A.R., Pobezhimov, V.V., Romanenko, D.A., Stolyarova, D.Y., Chvalun, S.N., and Grigoriev, T.E. (2025). A Comprehensive Mechanical Testing of Polyacrylamide Hydrogels: The Impact of Crosslink Density. Polymers, 17.","DOI":"10.3390\/polym17060737"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"3257","DOI":"10.1021\/acs.macromol.9b00032","article-title":"A Self-Healing and Highly Stretchable Polyelectrolyte Hydrogel via Cooperative Hydrogen Bonding as a Superabsorbent Polymer","volume":"52","author":"Su","year":"2019","journal-title":"Macromolecules"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"5613","DOI":"10.1039\/D5TB00050E","article-title":"Architecting a Partial-Thickness Cartilage Substitute with Tissue-Like Mechanics by Monomer Selection and Crosslinking in Tough Hydrogel Networks","volume":"13","author":"Dingus","year":"2025","journal-title":"J. Mater. Chem. B"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"De Piano, R., Caccavo, D., Barba, A.A., and Lamberti, G. (2024). Swelling Behavior of Anionic Hydrogels: Experiments and Modeling. Gels, 10.","DOI":"10.3390\/gels10120813"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1055\/a-2228-4757","article-title":"Polyampholyte Hydrogels with pH-Dependent Swelling for Controlled Catch\u2013Release of Model Dyes","volume":"6","author":"Mohotti","year":"2024","journal-title":"Org. Mater."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Sim\u00f5es, B., Rebelo, R.C., Ledesma, S., Pereira, P., Moreira, R., Ferreira, B.C., Coelho, J.F.J., and Serra, A.C. (2025). Development of Polyampholyte Cellulose-Based Hydrogels for Diapers with Improved Biocompatibility. Gels, 11.","DOI":"10.3390\/gels11040282"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Zhang, J., Wang, Y., Wei, Q., Wang, Y., Lei, M., Li, M., Li, D., Zhang, L., and Wu, Y. (2021). Self-Healing Mechanism and Conductivity of the Hydrogel Flexible Sensors: A Review. Gels, 7.","DOI":"10.3390\/gels7040216"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Roca-Arroyo, A.F., Gutierrez-Rivera, J.A., Morton, L.D., and Castilla-Casadiego, D.A. (2025). Hydrogel Network Architecture Design Space: Impact on Mechanical and Viscoelastic Properties. Gels, 11.","DOI":"10.3390\/gels11080588"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"18960","DOI":"10.1039\/D3CP00667K","article-title":"Effect of the Degree of Polymerization and Water Content on the Thermal Transport Phenomena in PEGDA Hydrogel: A Molecular-Dynamics-Based Study","volume":"25","author":"Kumar","year":"2023","journal-title":"Phys. Chem. Chem. Phys."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Yang, P., Boer, G., Snow, F., Williamson, A., Cheeseman, S., Samarasinghe, R.M., Rifai, A., Priyam, A., Elnathan, R., and Guijt, R. (2025). Test and Tune: Evaluating, Adjusting and Optimising the Stiffness of Hydrogels to Influence Cell Fate. Chem. Eng. J., 505.","DOI":"10.1016\/j.cej.2025.159295"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"37687","DOI":"10.1021\/acsomega.4c02475","article-title":"Stimuli-Responsive Phosphate Hydrogel: A Study on Swelling Behavior, Mechanical Properties, and Application in Expansion Microscopy","volume":"9","author":"Leng","year":"2024","journal-title":"ACS Omega"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Yelemessova, G., Gussenov, I., Ayazbayeva, A., Shakhvorostov, A., Orazzhanova, L., Klivenko, A., and Kudaibergenov, S. (2024). Preparation and Characterization of Preformed Polyelectrolyte and Polyampholyte Gel Particles for Plugging of High-Permeability Porous Media. Gels, 10.","DOI":"10.3390\/gels10090562"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Choi, S., Pyo, M., Lee, S., Jeong, Y., Nam, Y., Park, S., Jang, Y.-A., Kim, K., and Park, C.H. (2025). Engineering Thermo-Responsive Hydrogels with Tailored Mechanics for Biomedical Integration. Polymers, 17.","DOI":"10.3390\/polym17172424"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"6886","DOI":"10.1038\/s41467-024-51219-7","article-title":"Dehydration Regulates Structural Reorganization of Dynamic Hydrogels","volume":"15","author":"Xu","year":"2024","journal-title":"Nat. Commun."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Karageorgos, F.F., Alexiou, M., Tsoulfas, G., and Alexopoulos, A.H. (2024). Hydrogel-Based Vascularized Organ Tissue Engineering: A Systematized Review on Abdominal Organs. Gels, 10.","DOI":"10.3390\/gels10100653"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"151249","DOI":"10.1016\/j.cej.2024.151249","article-title":"Synergic Enhancement of Multifunctional Performance in Tough Multi-Network Hydrogels with Multi-Level Dynamic Hydrogen Bonds","volume":"489","author":"Wang","year":"2024","journal-title":"Chem. Eng. J."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"2307404","DOI":"10.1002\/advs.202307404","article-title":"Tough Hydrogels for Load-Bearing Applications","volume":"11","author":"Mommer","year":"2024","journal-title":"Adv. Sci."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"7448","DOI":"10.1039\/D4SM00882K","article-title":"Tough Supramolecular Hydrogels of Poly(N,N-Dimethylacrylamide)-Grafted Poly(Methacrylic Acid) with Cooperative Hydrogen Bonds as Physical Crosslinks","volume":"20","author":"Ma","year":"2024","journal-title":"Soft Matter"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"7244","DOI":"10.1039\/D5MH00588D","article-title":"Toughening Hydrogels with Small Molecules: Tiny Matter, Big Impact","volume":"12","author":"Sha","year":"2025","journal-title":"Mater. Horiz."},{"key":"ref_47","first-page":"126553","article-title":"Effect of Hydrogen Bonding Strength on the Structure and Properties of Hydrogels","volume":"287","author":"Xi","year":"2025","journal-title":"Polymer"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"111456","DOI":"10.1016\/j.compositesb.2024.111456","article-title":"Non-Swelling Polyelectrolyte Complex Hydrogels with Tissue-Matchable Mechanical Properties for Versatile Wet Wound Closure","volume":"279","author":"Li","year":"2024","journal-title":"Compos. Part B Eng."}],"container-title":["Gels"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2310-2861\/11\/12\/941\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T17:39:54Z","timestamp":1764092394000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2310-2861\/11\/12\/941"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,24]]},"references-count":48,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2025,12]]}},"alternative-id":["gels11120941"],"URL":"https:\/\/doi.org\/10.3390\/gels11120941","relation":{},"ISSN":["2310-2861"],"issn-type":[{"value":"2310-2861","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,24]]}}}