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Hou LX, Ding H, Hao XP, Zhu CN, Du M, Wu ZL, Zheng Q. Multi-level encryption of information in morphing hydrogels with patterned fluorescence. Soft Matter 2022; 18:2149-2156. [PMID: 35212340 DOI: 10.1039/d2sm00083k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Fluorescent hydrogels have attracted tremendous attention recently in the field of information security due to the booming development of information technology. Along this line, it is highly desired to improve the security level of concealed information by the advancements of materials and encryption technologies. Here we report multi-level encryption of information in a bilayer hydrogel with shape-morphing ability and patterned fluorescence. This hydrogel is composed of a fluorescence layer containing chromophore units in the poly(acrylic acid) network and an active layer with UV-absorption agents in the poly(N-isopropylacrylamide-co-acrylic acid) network. The former layer exhibits tunable fluorescence tailored by UV light irradiation to induce unimer-to-dimer transformation of the chromophores, facilitating the write-in of information through photolithography. The latter layer is responsive to temperature, enabling morphing of the bilayer hydrogel. Therefore, the bilayer hydrogel encoded with patterned fluorescent patterns can deform into three-dimensional configurations at room temperature to conceal the information, which is readable only after successive procedures of shape recovery at an appropriate temperature and under UV light irradiation from the right direction. The combination of morphing materials and patterned fluorescence as a new avenue to improve the encryption level of information should merit the design of other smart materials with integrated functions for specific applications.
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Affiliation(s)
- Li Xin Hou
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Hongyao Ding
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Xing Peng Hao
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Chao Nan Zhu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Miao Du
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Qiang Zheng
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
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Ju H, Zhu CN, Wang H, Page ZA, Wu ZL, Sessler JL, Huang F. Paper without a Trail: Time-Dependent Encryption using Pillar[5]arene-Based Host-Guest Invisible Ink. Adv Mater 2022; 34:e2108163. [PMID: 34802162 DOI: 10.1002/adma.202108163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/16/2021] [Indexed: 06/13/2023]
Abstract
A stimuli-responsive invisible ink for time-dependent encryption of information is reported. Consisting of a pillar[5]arene-based supramolecular network grafted with spiropyran moieties, these materials display time-dependent photochromic behavior with tailorable fading rates. Ultraviolet (UV) light results in isomerization of the colorless spiropyran to the corresponding colored merocyanine, while visible light or heat causes the reverse isomerization with a rate that is dependent on the density of host-guest crosslinks. The kinetics of discoloration are a function of merocyanine aggregation, which becomes more pronounced as the host-guest crosslink density is increased, leading to a reduced conversion rate and slower time-dependent fading. The degree of crosslinking, and hence the fading rate, may be modulated via the addition of unbound pillar[5]arene host or nitrile guest as competitors. Time-dependent information encryption is enabled by combining selective placement of host and guest competitors and UV patterning. UV patterning provides an initially "false" image that does not reveal the desired information, and it is only after a given time that the encrypted data appears. This work provides a unique approach to enhance the security of information storage associated with offline portable data encryption.
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Affiliation(s)
- Huaqiang Ju
- State Key Laboratory of Chemical Engineering, Key Laboratory of Excited-State Materials of Zhejiang Province, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Chao Nan Zhu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Hu Wang
- State Key Laboratory of Chemical Engineering, Key Laboratory of Excited-State Materials of Zhejiang Province, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Zachariah A Page
- Department of Chemistry, 105 East 24th Street, Stop A5300, The University of Texas at Austin, Austin, TX, 78712, United States
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jonathan L Sessler
- Department of Chemistry, 105 East 24th Street, Stop A5300, The University of Texas at Austin, Austin, TX, 78712, United States
| | - Feihe Huang
- State Key Laboratory of Chemical Engineering, Key Laboratory of Excited-State Materials of Zhejiang Province, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, 311215, China
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China
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Zhu CN, Zheng SY, Qiu HN, Du C, Du M, Wu ZL, Zheng Q. Plastic-Like Supramolecular Hydrogels with Polyelectrolyte/Surfactant Complexes as Physical Cross-links. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00835] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Chao Nan Zhu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Si Yu Zheng
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hao Nan Qiu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Cong Du
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Miao Du
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Qiang Zheng
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
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Zhu CN, Bai T, Wang H, Ling J, Huang F, Hong W, Zheng Q, Wu ZL. Dual-Encryption in a Shape-Memory Hydrogel with Tunable Fluorescence and Reconfigurable Architecture. Adv Mater 2021; 33:e2102023. [PMID: 34081366 DOI: 10.1002/adma.202102023] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/01/2021] [Indexed: 05/07/2023]
Abstract
Materials capable of shape-morphing and/or fluorescence imaging have practical significances in the fields of anti-counterfeiting, information display, and information protection. However, it's challenging to realize these functions in hydrogels due to the poor mechanical properties and lack of tunable fluorescence. A tough hydrogel with good shape-memory ability and phototunable fluorescence is reported here, which affords reprogrammable shape designing and information encoding for dual-encryption. This hydrogel is prepared by incorporating donor-acceptor chromophore units into a poly(1-vinylimidazole-co-methacrylic acid) network, in which the dense intra- and interchain hydrogen bonds lead to desirable features including high stiffness, high toughness, and temperature-mediated shape-memory property. Additionally, the hydrogel shows photomediated tunable fluorescence through a unimer-to-dimer transformation of the chromophores. By combining photolithography and origami/kirigami designs, hydrogel sheets encoded with fluorescent patterns can deform into specific 3D configurations. The geometrically encrypted fluorescent information in the architected hydrogels is readable only after sequential shape recovery and UV light irradiation. As demonstrated by proof-of-concept experiments, both the fluorescent pattern and the 3D configuration are reprogrammable, facilitating repeated information protection and display. The design of tough hydrogels with rewritable fluorescent patterns and reconfigurable shapes should guide the future development of smart materials with improved security and wider applications in aqueous environments.
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Affiliation(s)
- Chao Nan Zhu
- Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Tianwen Bai
- Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Hu Wang
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Jun Ling
- Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Feihe Huang
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Wei Hong
- Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Qiang Zheng
- Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zi Liang Wu
- Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
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Zhu CN, Li CY, Wang H, Hong W, Huang F, Zheng Q, Wu ZL. Reconstructable Gradient Structures and Reprogrammable 3D Deformations of Hydrogels with Coumarin Units as the Photolabile Crosslinks. Adv Mater 2021; 33:e2008057. [PMID: 33788313 DOI: 10.1002/adma.202008057] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 02/01/2021] [Indexed: 06/12/2023]
Abstract
Morphing hydrogels have versatile applications in soft robotics, flexible electronics, and biomedical devices. Controlling component distribution and internal stress within a hydrogel is crucial for shape-changing. However, existing gradient structures of hydrogels are usually non-reconstructable, once encoded by chemical reactions and covalent bonds. Fabricating hydrogels with distinct gradient structures is inevitable for every new configuration, resulting in poor reusability, adaptability, and sustainability that are disadvantageous for diverse applications. Herein, a hydrogel containing reversible photo-crosslinks that enable reprogramming of the gradient structures and 3D deformations into various configurations is reported. The hydrogel is prepared by micellar polymerization of hydrophobic coumarin monomer and hydrophilic acrylic acid. The presence of hexadecyltrimethylammonium chloride micelles increases the local concentration of coumarin units and also improves the mechanical properties of the hydrogel by forming robust polyelectrolyte/surfactant complexes that serve as the physical crosslinks. High-efficiency photodimerization and photocleavage reactions of coumarins are realized under 365 and 254 nm light irradiation, respectively, affording reversible tuning of the network structure of the hydrogel. Through photolithography, different gradient structures are sequentially patterned in one hydrogel that direct the deformations into distinct configurations. Such a strategy should be applicable for other photolabile hydrogels toward reprogrammable control of network structures and versatile functions.
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Affiliation(s)
- Chao Nan Zhu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Chen Yu Li
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Hu Wang
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance and Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Wei Hong
- Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Feihe Huang
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance and Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Qiang Zheng
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
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Wang H, Zhu CN, Zeng H, Ji X, Xie T, Yan X, Wu ZL, Huang F. Reversible Ion-Conducting Switch in a Novel Single-Ion Supramolecular Hydrogel Enabled by Photoresponsive Host-Guest Molecular Recognition. Adv Mater 2019; 31:e1807328. [PMID: 30694589 DOI: 10.1002/adma.201807328] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 01/16/2019] [Indexed: 05/27/2023]
Abstract
A novel ion-conducting supramolecular hydrogel with reversible photoconductive properties in which the azobenzene motif, α-cyclodextrin (α-CD), and ionic liquid are grafted onto the gel matrix is reported. Host-guest interactions with different association constants between α-CD and azobenzene or the anionic part of the ionic liquid can be readily tuned by photoinduced trans-cis isomerization of the azobenzene unit. When irradiated by 365 nm light, α-CD prefers to form a complex with the anionic part of the ionic liquid, resulting in decreased ionic mobility and thus high resistance of the hydrogel. However, under 420 nm light irradiation, a more stable complex is again formed between α-CD and trans-azobenzene, thereby releasing the bound anions to regenerate the low-resistive hydrogel. As such, remote control of the ionic conductivity of the hydrogel is realized by simple host-guest chemistry. With the incorporation of a logic gate, this hydrogel is able to reversibly switch an electric circuit on and off by light irradiation with certain wavelengths. The concept of photoswitchable ionic conductivity of a hydrogel mediated by competitive molecular recognition is potentially promising toward the fabrication of optoelectronic devices and applications in bioelectronic technology.
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Affiliation(s)
- Hu Wang
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance and Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Chao Nan Zhu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Hong Zeng
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance and Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Xiaofan Ji
- Department of Chemistry, The University of Texas at Austin, 105 East 24th Street, Stop A5300, AustinTX, 78712, USA
| | - Tao Xie
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Xuzhou Yan
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Feihe Huang
- State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance and Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China
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Zhu CN, Bai T, Wang H, Bai W, Ling J, Sun JZ, Huang F, Wu ZL, Zheng Q. Single Chromophore-Based White-Light-Emitting Hydrogel with Tunable Fluorescence and Patternability. ACS Appl Mater Interfaces 2018; 10:39343-39352. [PMID: 30351900 DOI: 10.1021/acsami.8b12619] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Bioluminescence is widespread in nature such as the jellyfish, which inspires scientists to design polymer hydrogels with tunable fluorescence. However, it remains a big challenge to develop white-light-emitting hydrogels with local tunability of the fluorescent behavior. Herein, we report a white fluorescent hydrogel prepared by one-pot micellar copolymerization of hydrophilic acrylamide and hydrophobic single donor-acceptor chromophore monomer, in which the unimer and the dimer of the chromophore coexist and generate high- and low-energy emission, respectively, under excitation. The fluorescent behavior of the hydrogel can be well tuned by phototreatment or heat treatment that induces unimer-to-dimer transformation of the chromophore and thus variation of the fluorescent color from blue to white and then to yellow. The fluorescence can also be reversibly switched off by forming terpyridine-Cu2+ chelate complexes and recovered by using chelating agent to extract the Cu2+ ions out of the gel matrix. These properties afford patterning the fluorescent hydrogel, which is transparent under daylight yet shows the pattern under ultraviolet light. These patterned fluorescent hydrogels should find applications in protected message display for improved information security.
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Wang ZJ, Zhu CN, Hong W, Wu ZL, Zheng Q. Cooperative deformations of periodically patterned hydrogels. Sci Adv 2017; 3:e1700348. [PMID: 28929134 PMCID: PMC5600534 DOI: 10.1126/sciadv.1700348] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 08/16/2017] [Indexed: 05/19/2023]
Abstract
Nature has shown elegant paradigms of smart deformation, which inspired biomimetic systems with controllable bending, folding, and twisting that are significant for the development of soft electronics and actuators. Complex deformations are usually realized by additively incorporating typical structures in selective domains with little interaction. We demonstrate the cooperative deformations of periodically patterned hydrogel sheets, in which neighboring domains mutually interact and cooperatively deform. Nonswelling disc gels are periodically positioned in a high-swelling gel. During the swelling process, the compartmentalized high-swelling gel alternately bends upward or downward to relieve the in-plane compression, but the overall integrated structure remains flat. The synergy between the elastic mismatch and the geometric periodicity selects the outcome pattern. Both experiment and modeling show that various types of cooperative deformation can be achieved by tuning the pattern geometry and gel properties. Different responsive polymers can also be patterned in one composite gel. Under stimulation, reversible transformations between different cooperative deformations are realized. The principle of cooperative deformation should be applicable to other materials, and the patterns can be miniaturized to the micrometer- or nanometer-scale level, providing the morphing materials with advanced functionalities for applications in various fields.
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Affiliation(s)
- Zhi Jian Wang
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Chao Nan Zhu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Wei Hong
- Department of Aerospace Engineering, Iowa State University, Ames, IA 50010, USA
- Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China
- Global Station for Soft Matter, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo 060-0810, Japan
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Qiang Zheng
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
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Wang ZJ, Zhu CN, Hong W, Wu ZL, Zheng Q. Programmed planar-to-helical shape transformations of composite hydrogels with bioinspired layered fibrous structures. J Mater Chem B 2016; 4:7075-7079. [PMID: 32263643 DOI: 10.1039/c6tb02178f] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Self-shaping materials have attracted tremendous interest due to their promising applications in soft robotics, and flexible electronics, etc. In this field, a crucial issue is how to construct complex yet elaborate structures in active materials. Here, we present the fabrication of composite hydrogels with both in-plane and out-of-plane structural gradients by multi-step photolithography and the resulting controllable deformations. A patterned gel with a layered fibrous structure like bean pod is developed, which shows programmed deformations from a flat shape to a twisted helix. The parameters of the helix can be deliberately tuned. This approach enables patterning different responsive polymers in specific regions of composite gels, leading to multiple shape transformations under stimulations. The controllability of intricate structures, together with tunable responses of localized gels, facilitates the generation of complex internal stresses and three-dimensional deformations of composite gels toward specific applications.
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Affiliation(s)
- Zhi Jian Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
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Sun B, Zhu CN. [Ultrastructural study of neonatal lungs with respiratory distress syndrome]. Zhonghua Bing Li Xue Za Zhi 1987; 16:304-5, 56. [PMID: 2968172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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