DMSO-Regulated PVA/Guar Gum Dual-Network Conductive Hydrogel for Wearable Strain Sensing

Abstract

Conductive hydrogels are vital components in modern electronics and show great promise for wearable sensors. However, their practical use is often limited by the difficulty of balancing mechanical properties and ionic/electronic conductivity. Herein, a dimethyl sulfoxide (DMSO)–regulated polyvinyl alcohol/guar gum (PVA/GG) dual-network conductive hydrogel (D-PVA/GG) was developed. The pre-shielding of intramolecular hydrogen bonds by DMSO induces extended polymer chain conformations, promoting the formation of a robust network and increasing the availability of hydrated hydroxyl groups. This mechanism significantly enhances both the mechanical performance and ionic conductivity of D-PVA/GG. Consequently, D-PVA/GG achieves a tensile strength of 3.82 MPa and a fracture strain of 815%. This strain is five times that of pure PVA hydrogels. D-PVA/GG also attained a conductivity of 1.66 S/m. These results demonstrate the synergistic optimization of the mechanical strength and conductivity. As a wearable sensor, D-PVA/GG can effectively monitor human motions in real time.

Keywords

Polyvinyl alcohol / Ionic conductive hydrogels / Dual-network / Strain sensor

References

[1] Mo F, Lin Y, Liu Y, et al. . Advances in ionic conductive hydrogels for skin sensor applications. Mater Sci Eng R Rep, 2025, 165100989

[2] Xu J, Zhu X, Zhao J, et al. . Biomedical applications of supramolecular hydrogels with enhanced mechanical properties. Adv Colloid Interface Sci, 2023, 321103000

[3] Tian T, Han H, Lin X, et al. . Luminescent nanofibers for human skin textures photocopying. Nat Commun, 2025, 16(1): 9720

[4] Han ST, Peng H, Sun Q, et al. . An overview of the development of flexible sensors. Adv Mater, 2017, 29(33): 1700375

[5] Liu Y, Zhang J, Wang D. Preparation schemes and applications of multifunctional PVA composite hydrogels. Chem Eng J, 2025, 508160946

[6] Xu Q, Wu Z, Zhao W, et al. . Strategies in the preparation of conductive polyvinyl alcohol hydrogels for applications in flexible strain sensors, flexible supercapacitors, and triboelectric nanogenerator sensors: an overview. Adv Compos Hybrid Mater, 2023, 6(6): 203

[7] Zhang L, Jiang D, Dong T, et al. . Overview of ionogels in flexible electronics. Chem Rec, 2020, 20(9): 948-967

[8] Tang L, Wu S, Qu J, et al. . A review of conductive hydrogel used in flexible strain sensor. Materials Basel, 2020, 13(18): 3947

[9] He Q, Zhong Y, Li J, et al. . Constructing kosmotropic salt-compatible PVA hydrogels for stable zinc anodes via strong hydrogen bonds preshielding effect. Adv Energy Mater, 2024, 14(23): 2400170

[10] Mo F, Zhou P, Lin S, et al. . A review of conductive hydrogel‐based wearable temperature sensors. Adv Healthc Mater, 2024, 13(26): 2401503

[11] Chen J, Liu F, Abdiryim T, et al. . An overview of conductive composite hydrogels for flexible electronic devices. Adv Compos Hybrid Mater, 2024, 7(2): 35

[12] Li M, Wang Y, Wei Q, et al. . Hydrophobic associations and cellulose nanofibers reinforced PVA/PAM multi-network conductive hydrogel with high sensitivity, fast response, and excellent mechanical properties. Carbohydr Polym, 2025, 368124225

[13] Chen Z, Chen Y, Hedenqvist MS, et al. . Multifunctional conductive hydrogels and their applications as smart wearable devices. J Mater Chem B, 2021, 9(11): 2561-2583

[14] Li G, Huang K, Deng J, et al. . Highly conducting and stretchable double‐network hydrogel for soft bioelectronics. Adv Mater, 2022, 34(15): 2200261

[15] Ullah R, Shah LA, Khan M, et al. . Guar gum reinforced conductive hydrogel for strain sensing and electronic devices. Int J Biol Macromol, 2023, 246125666

[16] Verma D, Sharma SK. Recent advances in guar gum based drug delivery systems and their administrative routes. Int J Biol Macromol, 2021, 181: 653-671

[17] Zhuo H, Dong X, Liu Q, et al. . Bamboo-inspired ultra-strong nanofiber-reinforced composite hydrogels. Nat Commun, 2025, 16(1): 980

[18] Thombare N, Jha U, Mishra S, et al. . Borax cross-linked guar gum hydrogels as potential adsorbents for water purification. Carbohydr Polym, 2017, 168: 274-281

[19] Li N, Liu C, Chen W, et al. . Facile access to guar gum based supramolecular hydrogels with rapid self-healing ability and multistimuli responsive gel–sol transitions. J Agric Food Chem, 2018, 67(2): 746-752

[20] Pan X, Wang Q, Ning D, et al. . Ultraflexible self-healing guar gum-glycerol hydrogel with injectable, antifreeze, and strain-sensitive properties. ACS Biomater Sci Eng, 2018, 4(9): 3397-3404

[21] Pettignano A, Grijalvo S, Haering M, et al. . Boronic acid-modified alginate enables direct formation of injectable, self-healing and multistimuli-responsive hydrogels. Chem Commun, 2017, 53(23): 3350-3353

[22] Adelnia H, Ensandoost R, Moonshi SS, et al. . Freeze/thawed polyvinyl alcohol hydrogels: present, past and future. Eur Polym J, 2022, 164110974

[23] Yu H, Zhao L, Wang L, et al. . Double-network PVA/gelatin/borax hydrogels with self-healing, strength, stretchable, stable, and transparent properties. J Appl Polym Sci, 2023, 140(20): e53852

[24] Li CY, Wang JL, Zhang DT, et al. . In-situ physical/chemical cross-linked hydrogel electrolyte achieving ultra-stable zinc anode-electrolyte interface towards dendrite-free zinc ion battery. J Energy Chem, 2024, 97: 342-351

[25] Liu X, Wu Z, Jiang D, et al. . A highly stretchable, sensing durability, transparent, and environmentally stable ion conducting hydrogel strain sensor built by interpenetrating Ca²⁺-SA and glycerol-PVA double physically cross-linked networks. Adv Compos Hybrid Mater, 2022, 5(3): 1712-1729

[26] Wang L, Ago M, Borghei M, et al. . Conductive carbon microfibers derived from wet-spun lignin/nanocellulose hydrogels. ACS Sustain Chem Eng, 2019, 7(6): 6013-6022

[27] Xia P, Zhang W, Peng C, et al. . A high-order double network hydrogel. Macromolecules, 2024, 57(23): 11251-11265

[28] Li X, Gong JP. Design principles for strong and tough hydrogels. Nat Rev Mater, 2024, 9(6): 380-398

[29] Han S, Hu Y, Wei J, et al. . A semi-interpenetrating poly(ionic liquid) network-driven low hysteresis and transparent hydrogel as a self-powered multifunctional sensor. Adv Funct Mater, 2024, 34(32): 2401607

[30] Lei T, Wang Y, Zhang Q, et al. . Ultra-stretchable and anti-freezing ionic conductive hydrogels as high performance strain sensors and flexible triboelectric nanogenerator in extreme environments. Nano Energy, 2024, 126109633

[31] Yan Y, Duan S, Liu B, et al. . Tough hydrogel electrolytes for anti‐freezing zinc‐ion batteries. Adv Mater, 2023, 35(18): 2211637

[32] Wang Y, Li Q, Hong H, et al. . Lean-water hydrogel electrolyte for zinc ion batteries. Nat Commun, 2023, 14(1): 3890

[33] Luo Y, Yu M, Zhang Y, et al. . Highly sensitive strain sensor and self-powered triboelectric nanogenerator using a fully physical crosslinked double-network conductive hydrogel. Nano Energy, 2022, 104107955

[34] Zhao Y, Zhang X, Hao Y, et al. . Multifunctional PVA/PNIPAM conductive hydrogel sensors enabled human-machine interaction intelligent rehabilitation training. Adv Compos and Hybrid Mater, 2024, 7(6): 245

[35] Zheng B, Zhou H, Wang Z, et al. . Fishing net‐inspired mutiscale ionic organohydrogels with outstanding mechanical robustness for flexible electronic devices. Adv Funct Mater, 2023, 33(28): 2213501

[36] Wen J, Tang J, Ning H, et al. . Multifunctional ionic skin with sensing, UV‐filtering, water‐retaining, and anti‐freezing capabilities. Adv Funct Mater, 2021, 31(21): 2011176

[37] Li S, Cheng Y, Deng K, et al. . A self-powered flexible tactile sensor utilizing chemical battery reactions to detect static and dynamic stimuli. Nano Energy, 2024, 124109461

[38] He S, Fang H, Liu J, et al. . Fabrication of anti-freezing and self-healing hydrogel sensors based on carboxymethyl guar gum and poly(ionic liquid). Int J Biol Macromol, 2024, 279135112

[39] Chan CY, Wang Z, Li Y, et al. . Single-ion conducting double-network hydrogel electrolytes for long cycling zinc-ion batteries. ACS Appl Mater Interfaces, 2021, 13(26): 30594-30602

[40] Liu Q, Yu Z, Zhuang Q, et al. . Anti‐fatigue hydrogel electrolyte for all‐flexible Zn‐ion batteries. Adv Mater, 2023, 35(36): 2300498

[41] Liu Y, Gao A, Hao J, et al. . Soaking-free and self-healing hydrogel for wearable zinc-ion batteries. Chem Eng J, 2023, 452139605

[42] Ma C, Hou D, Jiang J, et al. . Elucidating the synergic effect in nanoscale MoS₂/TiO₂ heterointerface for Na‐ion storage. Adv Sci, 2022, 9(35): 2204837

[43] Li K, Yang X, Dong X, et al. . Easy regulation of chitosan-based hydrogel microstructure with citric acid as an efficient buffer. Carbohydr Polym, 2023, 300120258

[44] Wang Q, Sun Z, Zhang Z, et al. . Strong and tough chitosan-based conductive hydrogels cross-linked by dual ionic networks for flexible strain sensors. Int J Biol Macromol, 2025, 315144498

[45] Lei T, Pan J, Wang N, et al. . Cold-resistant, highly stretchable ionic conductive hydrogels for intelligent motion recognition in winter sports. Mater Horiz, 2024, 11(5): 1234-1250

[46] Zou X, Wang X, Bai Z, et al. . Environment-tolerant versatile ion-conductive eutectic hydrogels for self-powered wearable flexible sensors. Chem Eng J, 2023, 463142349

RIGHTS & PERMISSIONS

The Author(s)