Abstract
Human muscles are notably toughened or softened with specific inorganic ions. Inspired by this phenomenon, herein we report a simple strategy to endow hydrogels with comparable ion-responsive mechanical properties by treating the gels with different ionic solutions. Semi-crystalline poly(vinyl alcohol) hydrogels are chosen as examples to illustrate this concept. Similar to muscles, the mechanical property of hydrogels demonstrates strong dependence on both the nature and concentration of inorganic ions. Immersed at the same salt concentration, the hydrogels treated with different ionic solutions manifest a broad-range tunability in rigidity (Young’s modulus from 0.16 to 9.6 MPa), extensibility (elongation ratio from 100% to 570%), and toughness (fracture work from 0.82 to 35 MJ m−3). The mechanical property well follows the Hofmeister series, where the “salting-out” salts (kosmotropes) have a more pronounced effect on the reinforcement of the hydrogels. Besides, the hydrogels’ mechanical performance exhibits a positive correlation with the salt concentration. Furthermore, it is revealed both the polymer solubility from amorphous domains and polymer crystallinity from crystalline domains are significantly influenced by the ions, which synergistically contribute to the salt-responsive mechanical performance. Benefitting from this feature, the hydrogels have demonstrated promising industrial applications, including tunable tough engineering soft materials, anti-icing coatings, and soft electronic devices.
摘要
肌肉组织可因特定离子的刺激而发生显著机械性能的变化. 受 此现象启发, 本文通过一种简单高效的策略, 赋予结晶型聚乙烯醇水凝 胶显著的盐响应性特征. 与肌肉组织类似, 这类水凝胶的机械性能展现 出强烈的离子种类及浓度的依赖关系. 经过相关浓度盐溶液处理后, 该 水凝胶在硬度(杨氏模量~0.16–9.6 MPa)、延展性(伸长率~100%–570%)和韧性(断裂功~0.82–35 MJm−3)方面表现出大范围的可调控性. 其机械性能的变化很好地遵循了霍夫迈斯特序列, 即强盐析性质的离 子(kosmotropes)在水凝胶增韧中彰明较著. 同时, 该水凝胶的机械性 能与盐溶液浓度表现出显著的正相关性. 实验证明, 离子可显著影响非 晶区的高分子水化程度和结晶区的聚合物结晶度, 进而协同调控水凝 胶的机械性能. 得益于此, 这类水凝胶在韧性可调工程软材料、防冰涂 料和柔性电子设备等领域展现出良好的应用前景.
Article PDF
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
References
Borkhvardt V. Muscle contraction: Theory and facts. Bio Comm, 2018, 63: 106–108
Montero de Espinosa L, Meesorn W, Moatsou D, et al. Bioinspired polymer systems with stimuli-responsive mechanical properties. Chem Rev, 2017, 117: 12851–12892
Calvert P. Hydrogels for soft machines. Adv Mater, 2009, 21: 743–756
Wang X, Ronsin O, Gravez B, et al. Nanostructured dense collagenpolyester composite hydrogels as amphiphilic platforms for drug delivery. Adv Sci, 2021, 8: 2004213
Qiu Y, Park K. Environment-sensitive hydrogels for drug delivery. Adv Drug Deliver Rev, 2001, 53: 321–339
Guo H, Sanson N, Marcellan A, et al. Thermoresponsive toughening in LCST-type hydrogels: Comparison between semi-interpenetrated and grafted networks. Macromolecules, 2016, 49: 9568–9577
Guo H, Nakajima T, Hourdet D, et al. Hydrophobic hydrogels with fruit-like structure and functions. Adv Mater, 2019, 31: 1900702
Guo H, Mussault C, Marcellan A, et al. Hydrogels with dual thermoresponsive mechanical performance. Macromol Rapid Commun, 2017, 38: 1700287
Dompé M, Cedano-Serrano FJ, Vahdati M, et al. Underwater adhesion of multiresponsive complex coacervates. Adv Mater Interfaces, 2020, 7: 1901785
Huang KT, Ishihara K, Huang CJ. Polyelectrolyte and anti-polyelectrolyte effects for dual salt-responsive interpenetrating network hydrogels. Biomacromolecules, 2019, 20: 3524–3534
Chen Q, Yan X, Zhu L, et al. Improvement of mechanical strength and fatigue resistance of double network hydrogels by ionic coordination interactions. Chem Mater, 2016, 28: 5710–5720
Yu HC, Li CY, Du M, et al. Improved toughness and stability of κ-carrageenan/polyacrylamide double-network hydrogels by dual cross-linking of the first network. Macromolecules, 2019, 52: 629–638
Das Mahapatra R, Imani KBC, Yoon J. Integration of macro-cross-linker and metal coordination: A super stretchable hydrogel with high toughness. ACS Appl Mater Interfaces, 2020, 12: 40786–40793
Henderson KJ, Zhou TC, Otim KJ, et al. Ionically cross-linked triblock copolymer hydrogels with high strength. Macromolecules, 2010, 43: 6193–6201
Fan H, Wang J, Tao Z, et al. Adjacent cationic-aromatic sequences yield strong electrostatic adhesion of hydrogels in seawater. Nat Commun, 2019, 10: 5127
Baldwin RL. How Hofmeister ion interactions affect protein stability. BioPhys J, 1996, 71: 2056–2063
Jungwirth P, Cremer PS. Beyond Hofmeister. Nat Chem, 2014, 6: 261–263
Gurau MC, Lim SM, Castellana ET, et al. On the mechanism of the Hofmeister effect. J Am Chem Soc, 2004, 126: 10522–10523
Guo H, de Magalhaes Goncalves M, Ducouret G, et al. Cold and hot gelling of alginate-graft-PNIPAM: A schizophrenic behavior induced by potassium salts. Biomacromolecules, 2018, 19: 576–587
Zhang Y, Furyk S, Bergbreiter DE, et al. Specific ion effects on the water solubility of macromolecules: PNIPAM and the Hofmeister series. J Am Chem Soc, 2005, 127: 14505–14510
Yasumoto N, Kasahara N, Sakaki A, et al. Ion-specific swelling behaviors of partially quaternized poly(4-vinyl pyridine) gel. Colloid Polym Sci, 2006, 284: 900–908
Tuncaboylu DC, Sari M, Oppermann W, et al. Tough and self-healing hydrogels formed via hydrophobic interactions. Macromolecules, 2011, 44: 4997–5005
Sun X, Luo C, Luo F. Preparation and properties of self-healable and conductive PVA-agar hydrogel with ultra-high mechanical strength. Eur Polym J, 2020, 124: 109465
Wu S, Hua M, Alsaid Y, et al. Poly(vinyl alcohol) hydrogels with broad-range tunable mechanical properties via the Hofmeister effect. Adv Mater, 2021, 33: 2007829
He Q, Huang Y, Wang S. Hofmeister effect-assisted one step fabrication of ductile and strong gelatin hydrogels. Adv Funct Mater, 2018, 28: 1705069
Lin J, Huang Y, Wang S. The Hofmeister effect on protein hydrogels with stranded and particulate microstructures. Colloids Surfs B-Biointerfaces, 2020, 196: 111332
Otsuka E, Suzuki A. A simple method to obtain a swollen PVA gel crosslinked by hydrogen bonds. J Appl Polym Sci, 2009, 114: 10–16
Obukhov SP, Rubinstein M, Colby RH. Network modulus and super-elasticity. Macromolecules, 1994, 27: 3191–3198
Guo H, Mussault C, Brûlet A, et al. Thermoresponsive toughening in LCST-type hydrogels with opposite topology: From structure to fracture properties. Macromolecules, 2016, 49: 4295–4306
Guo H, Sanson N, Hourdet D, et al. Thermoresponsive toughening with crack bifurcation in phase-separated hydrogels under isochoric conditions. Adv Mater, 2016, 28: 5857–5864
Demirörs AF, Arslan M, Dag Ö. The effect of anions of transition metal salts on the structure of modified mesostructured silica films and monoliths. Microporous Mesoporous Mater, 2007, 98: 249–257
Guo M, Wu Y, Xue S, et al. A highly stretchable, ultra-tough, remarkably tolerant, and robust self-healing glycerol-hydrogel for a dual-responsive soft actuator. J Mater Chem A, 2019, 7: 25969–25977
Lu C, Chen X. All-temperature flexible supercapacitors enabled by antifreezing and thermally stable hydrogel electrolyte. Nano Lett, 2020, 20: 1907–1914
Zhang L, Zhao J, Zhu J, et al. Anisotropic tough poly(vinyl alcohol) hydrogels. Soft Matter, 2012, 8: 10439–10447
Sun JY, Zhao X, Illeperuma WRK, et al. Highly stretchable and tough hydrogels. Nature, 2012, 489: 133–136
Haraguchi K, Takehisa T. Nanocomposite hydrogels: A unique organic-inorganic network structure with extraordinary mechanical, optical, and swelling/de-swelling properties. Adv Mater, 2002, 14: 1120–1124
Li J, Suo Z, Vlassak JJ. Stiff, strong, and tough hydrogels with good chemical stability. J Mater Chem B, 2014, 2: 6708–6713
Sun TL, Kurokawa T, Kuroda S, et al. Physical hydrogels composed of polyampholytes demonstrate high toughness and viscoelasticity. Nat Mater, 2013, 12: 932–937
Zhang HJ, Sun TL, Zhang AK, et al. Tough physical double-network hydrogels based on amphiphilic triblock copolymers. Adv Mater, 2016, 28: 4884–4890
Sakai T, Matsunaga T, Yamamoto Y, et al. Design and fabrication of a high-strength hydrogel with ideally homogeneous network structure from tetrahedron-like macromonomers. Macromolecules, 2008, 41: 5379–5384
Chen H, Yang F, Chen Q, et al. A novel design of multi-mechanoresponsive and mechanically strong hydrogels. Adv Mater, 2017, 29: 1606900
Lin P, Ma S, Wang X, et al. Molecularly engineered dual-crosslinked hydrogel with ultrahigh mechanical strength, toughness, and good self-recovery. Adv Mater, 2015, 27: 2054–2059
Gong JP, Katsuyama Y, Kurokawa T, et al. Double-network hydrogels with extremely high mechanical strength. Adv Mater, 2003, 15: 1155–1158
Little CJ, Bawolin NK, Chen X. Mechanical properties of natural cartilage and tissue-engineered constructs. Tissue Eng Part B-Rev, 2011, 17: 213–227
Acknowledgements
This work was supported by the National Natural Science Foundation of China (51903253), the Natural Science Foundation of Guangdong Province of China (2019A1515011150 and 2019A1515011258), and the Science and Technology Development Fund of Macao (FDCT 0083/2019/A2).
Author information
Authors and Affiliations
Contributions
Guo H and Wang X designed and supervised the study and revised the manuscript. Li P and Wang Z prepared the hydrogels and characterized their mechanical properties; Li P and Lin X contributed to the application of the hydrogels and the data analysis. Li P and Guo H wrote the manuscript. All the authors contributed to the general discussion.
Corresponding authors
Additional information
Ping Li is currently a master student at Sun Yat-sen University. His research interest mainly focuses on the development and applications of high-toughness hydrogel materials.
Xiaolin Wang obtained her PhD degree in 2015 from Sorbonne Université, Paris, France and worked for two more years in the same lab for her postdoctoral research. She joined the School of Pharmacy and State Key Laboratory of Quality Research in Chinese Medicines at Macau University of Science and Technology (MUST) as an assistant professor in 2018. Her current research interests are focused on the nano/microparticles and hydrogel-based drug delivery systems in the field of wound healing and cardiovascular diseases.
Hui Guo is an associate professor at Sun Yat-sen University, China. He graduated from Shanghai Jiao Tong University, China in 2012 and Universite Pierre et Marie Curie, France in 2015. Then he was engaged in two periods of postdoctoral research under the supervision of professors Dominique Hourdet and Jian Ping Gong before back to China. His current research interests include smart hydrogels, functional soft matters, and hydrogel-based biomedical applications.
Conflict of interest
The authors declare that they have no conflict of interest.
Supporting Information
40843_2021_1722_MOESM1_ESM.pdf
Muscle-inspired ion-sensitive hydrogels with highly tunable mechanical performance for versatile industrial applications
Rights and permissions
About this article
Cite this article
Li, P., Wang, Z., Lin, X. et al. Muscle-inspired ion-sensitive hydrogels with highly tunable mechanical performance for versatile industrial applications. Sci. China Mater. 65, 229–236 (2022). https://doi.org/10.1007/s40843-021-1722-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40843-021-1722-0