Touch-Responsive Hydrogel for Biomimetic Flytrap-Like Soft Actuator
Corresponding Author: Tao Chen
Nano-Micro Letters,
Vol. 14 (2022), Article Number: 182
Abstract
Stimuli-responsive hydrogel is regarded as one of the most promising smart soft materials for the next-generation advanced technologies and intelligence robots, but the limited variety of stimulus has become a non-negligible issue restricting its further development. Herein, we develop a new stimulus of “touch” (i.e., spatial contact with foreign object) for smart materials and propose a flytrap-inspired touch-responsive polymeric hydrogel based on supersaturated salt solution, exhibiting multiple responsive behaviors in crystallization, heat releasing, and electric signal under touch stimulation. Furthermore, utilizing flytrap-like cascade response strategy, a soft actuator with touch-responsive actuation is fabricated by employing the touch-responsive hydrogel and the thermo-responsive hydrogel. This investigation provides a facile and versatile strategy to design touch-responsive smart materials, enabling a profound potential application in intelligence areas.
Highlights:
1 A pioneering touch-responsive material with multiple responsiveness to touch stimulation (i.e., spatial contact with foreign object) is successfully developed.
2 The responsive behaviors of touch-responsive hydrogel exhibit excellent controllability and designability.
3 Based on cascade response strategy, a flytrap-like soft actuator with touch-responsive actuation is fabricated by employing the touch-responsive hydrogel.
Keywords
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References
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H.H. Shi, S.S. Wu, M.Q. Si, S.X. Wei, G.Q. Lin et al., Cephalopod-inspired design of photomechanically modulated display systems for on-demand fluorescent patterning. Adv. Mater. 34(4), 2107452 (2022). https://doi.org/10.1002/adma.202107452
X.P. Hao, Z. Xu, C.Y. Li, W. Hong, Q. Zheng et al., Kirigami-design-enabled hydrogel multimorphs with application as a multistate switch. Adv. Mater. 32(22), 2000781 (2020). https://doi.org/10.1002/adma.202000781
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L. Li, J.M. Scheiger, P.A. Levkin, Design and applications of photoresponsive hydrogels. Adv. Mater. 31(26), 1807333 (2019). https://doi.org/10.1002/adma.201807333
Z.X. Deng, R. Yu, B.L. Guo, Stimuli-responsive conductive hydrogels: design, properties, and applications. Mater. Chem. Front. 5(5), 2092–2123 (2021). https://doi.org/10.1039/d0qm00868k
Y.H. Chen, J.J. Yang, X. Zhang, Y.Y. Feng, H. Zeng et al., Light-driven bimorph soft actuators: design, fabrication, and properties. Mater. Horiz. 8(3), 728–757 (2021). https://doi.org/10.1039/d0mh01406k
E.M. White, J. Yatvin, J.B. Grubbs, J.A. Bilbrey, J. Locklin, Advances in smart materials: stimuli-responsive hydrogel thin films. J. Polym. Sci. Part B Polym. Phys. 51(14), 1084–1099 (2013). https://doi.org/10.1002/polb.23312
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D. Zhang, B.P. Ren, Y.X. Zhang, L.J. Xu, Q.Y. Huang et al., From design to applications of stimuli-responsive hydrogel strain sensors. J. Mater. Chem. B 8(16), 3171–3191 (2020). https://doi.org/10.1039/c9tb02692d
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C.X. Ma, W. Lu, X.X. Yang, J. He, X.X. Le et al., Bioinspired anisotropic hydrogel actuators with on-off switchable and color-tunable fluorescence behaviors. Adv. Funct. Mater. 28(7), 1704568 (2018). https://doi.org/10.1002/adfm.201704568
Z.J. Shao, S.S. Wu, Q. Zhang, H. Xie, T. Xiang et al., Salt-responsive polyampholyte-based hydrogel actuators with gradient porous structures. Polym. Chem. 12(5), 670–679 (2021). https://doi.org/10.1039/d0py01492c
L.Q. Hua, M.Q. Xie, Y.K. Jian, B.Y. Wu, C.Y. Chen et al., Multiple-responsive and amphibious hydrogel actuator based on asymmetric UCST-type volume phase transition. ACS Appl. Mater. Interfaces 11(46), 43641–43648 (2019). https://doi.org/10.1021/acsami.9b17159
Z.Y. Lei, Q.K. Wang, S.T. Sun, W.C. Zhu, P.Y. Wu, A bioinspired mineral hydrogel as a self-healable, mechanically adaptable ionic skin for highly sensitive pressure sensing. Adv. Mater. 29(22), 1700321 (2017). https://doi.org/10.1002/adma.201700321
D. Das, P. Ghosh, A. Ghosh, C. Haldar, S. Dhara et al., Stimulus-responsive, biodegradable, biocompatible, covalently cross-linked hydrogel based on dextrin and poly(N-isopropylacrylamide) for in vitro/in vivo controlled drug release. ACS Appl. Mater. Interfaces 7(26), 14338–14351 (2015). https://doi.org/10.1021/acsami.5b02975
Y.P. Wang, X.F. Cao, J. Cheng, B.W. Yao, Y.S. Zhao et al., Cephalopod-inspired chromotropic ionic skin with rapid visual sensing capabilities to multiple stimuli. ACS Nano 15(2), 3509–3521 (2021). https://doi.org/10.1021/acsnano.1c00181
B.F. Ding, P.Y. Zeng, Z.Y. Huang, L.X. Dai, T.S. Lan et al., A 2D material-based transparent hydrogel with engineerable interference colours. Nat. Commun. 13, 1212 (2022). https://doi.org/10.1038/s41467-021-26587-z
J.J. Wei, Y.F. Zheng, T. Chen, A fully hydrophobic ionogel enables highly efficient wearable underwater sensors and communicators. Mater. Horiz. 8(10), 2761–2770 (2021). https://doi.org/10.1039/d1mh00998b
J. Yeom, A. Choe, S. Lim, Y. Lee, S. Na et al., Soft and ion-conducting hydrogel artificial tongue for astringency perception. Sci. Adv. 6(23), eaba5785 (2020). https://doi.org/10.1126/sciadv.aba5785
Y.L. Zhang, W.Y. Zhao, S.H. Ma, H. Liu, X.W. Wang et al., Modulus adaptive lubricating prototype inspired by instant muscle hardening mechanism of catfish skin. Nat. Commun. 13, 377 (2022). https://doi.org/10.1038/s41467-022-28038-9
J.W. Huang, Y. Liu, Y.X. Yang, Z.J. Zhou, J. Mao et al., Electrically programmable adhesive hydrogels for climbing robots. Sci. Robot. 6(53), eabe1858 (2021). https://doi.org/10.1126/scirobotics.abe1858
Q.L. Zhu, C.F. Dai, D. Wagner, M. Daab, W. Hong et al., Distributed electric field induces orientations of nanosheets to prepare hydrogels with elaborate ordered structures and programmed deformations. Adv. Mater. 32(47), 2005567 (2020). https://doi.org/10.1002/adma.202005567
C.Y. Li, S.Y. Zheng, X.P. Hao, W. Hong, Q. Zheng et al., Spontaneous and rapid electro-actuated snapping of constrained polyelectrolyte hydrogels. Sci. Adv. 8(15), eabm9608 (2022). https://doi.org/10.1126/sciadv.abm9608
Q.L. Zhu, C.F. Dai, D. Wagner, O. Khoruzhenko, W. Hong et al., Patterned electrode assisted one-step fabrication of biomimetic morphing hydrogels with sophisticated anisotropic structures. Adv. Sci. 8(24), 2102353 (2021). https://doi.org/10.1002/advs.202102353
H. Na, Y.W. Kang, C.S. Park, S. Jung, H.Y. Kim et al., Hydrogel-based strong and fast actuators by electroosmotic turgor pressure. Science 376(6590), 301–307 (2022). https://doi.org/10.1126/science.abm7862
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