Robust Fabrication of Anisotropic Bilayer Hydrogel Embedded With a Gradient Structure in One Layer: Enhanced Temperature-Responsive Bending, Shape Programmability, and Actuator and Sensor Applications
Mulenga Kalulu
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Sustainable Chemistry and Environment Project, Department of Chemistry, The University of Zambia, Lusaka, Zambia
Contribution: Conceptualization (lead), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (lead), Visualization (lead), Writing - original draft (lead)
Search for more papers by this authorOnesmus Munyati
Sustainable Chemistry and Environment Project, Department of Chemistry, The University of Zambia, Lusaka, Zambia
Contribution: Resources (lead), Supervision (supporting), Writing - review & editing (supporting)
Search for more papers by this authorOlayinka Oderinde
Department of Chemistry, Faculty of Natural and Applied Sciences, Lead City University, Ibadan, Nigeria
Contribution: Validation (supporting), Writing - review & editing (lead)
Search for more papers by this authorJun Hu
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Contribution: Data curation (supporting), Validation (supporting)
Search for more papers by this authorShephrah O. Ogungbesan
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Search for more papers by this authorCorresponding Author
Guodong Fu
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Correspondence:
Guodong Fu ([email protected]; [email protected])
Contribution: Funding acquisition (lead), Project administration (lead), Supervision (lead)
Search for more papers by this authorMulenga Kalulu
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Sustainable Chemistry and Environment Project, Department of Chemistry, The University of Zambia, Lusaka, Zambia
Contribution: Conceptualization (lead), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (lead), Visualization (lead), Writing - original draft (lead)
Search for more papers by this authorOnesmus Munyati
Sustainable Chemistry and Environment Project, Department of Chemistry, The University of Zambia, Lusaka, Zambia
Contribution: Resources (lead), Supervision (supporting), Writing - review & editing (supporting)
Search for more papers by this authorOlayinka Oderinde
Department of Chemistry, Faculty of Natural and Applied Sciences, Lead City University, Ibadan, Nigeria
Contribution: Validation (supporting), Writing - review & editing (lead)
Search for more papers by this authorJun Hu
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Contribution: Data curation (supporting), Validation (supporting)
Search for more papers by this authorShephrah O. Ogungbesan
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Search for more papers by this authorCorresponding Author
Guodong Fu
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu, People's Republic of China
Correspondence:
Guodong Fu ([email protected]; [email protected])
Contribution: Funding acquisition (lead), Project administration (lead), Supervision (lead)
Search for more papers by this authorFunding: This work was supported by the National Natural Science Foundation of China (52073059).
ABSTRACT
Anisotropic hydrogel actuators with gradient structures offer tunable mechanical properties, like directional stiffness or bending. However, creating these gradient-structured bilayer hydrogels is challenging, as current methods rely on complex, single-force programming. Developing a double-actuating bilayer hydrogel with temperature-responsive and auxiliary layers could address these limitations and enhance their applicability. In this study, an anisotropic hydrogel actuator was developed using a simple, cost-effective method to create a unique multi-asymmetric structure with an embedded gradient in one layer. The resulting hydrogels exhibited excellent temperature-responsive bending (360° within 9 s) and adaptive, complex shape-programmable deformation (2D letters, flowers, butterflies, leaves). In addition, the hydrogels demonstrated good shape memory, mechanical strength, and conductivity. Prototypes of a hydrogel gripper and humidity alarm were successfully fabricated, showcasing the potential of this strategy for designing smart hydrogels for applications in sensors, smart humidity alarms, grippers, and actuators.
Conflicts of Interest
The authors declare no conflicts of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available upon reasonable request from the corresponding author.
Supporting Information
| Filename | Description |
|---|---|
| app56707-sup-0001-VideoS1.mp4MPEG-4 video, 9.6 MB |
Video S1. Macroscopic demonstration of the anisotropic bending behavior of a PNAM bilayer hydrogel in an aqueous environment at 50°C. |
| app56707-sup-0002-VideoS2.mp4MPEG-4 video, 3 MB |
Video S2. Macroscopic demonstration of the conductivity performance of a PNAM bilayer hydrogel in illuminating an LED light. |
| app56707-sup-0003-Supinfo.docxWord 2007 document , 1.5 MB |
Data S1. Supporting Information. |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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