1
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Liang H, Zhang Y, He E, Yang Y, Liu Y, Xu H, Yang Z, Wang Y, Wei Y, Ji Y. "Cloth-to-Clothes-Like" Fabrication of Soft Actuators. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2400286. [PMID: 38722690 DOI: 10.1002/adma.202400286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 04/20/2024] [Indexed: 05/16/2024]
Abstract
Inspired by adaptive natural organisms and living matter, soft actuators appeal to a variety of innovative applications such as soft grippers, artificial muscles, wearable electronics, and biomedical devices. However, their fabrication is typically limited in laboratories or a few enterprises since specific instruments, strong stimuli, or specialized operation skills are inevitably involved. Here a straightforward "cloth-to-clothes-like" method to prepare soft actuators with a low threshold by combining the hysteretic behavior of liquid crystal elastomers (LCEs) with the exchange reaction of dynamic covalent bonds, is proposed. Due to the hysteretic behavior, the LCEs (resemble "cloth") effectively retain predefined shapes after stretching and releasing for extended periods. Subsequently, the samples naturally become soft actuators (resemble "clothes") via the exchange reaction at ambient temperatures. As a post-synthesis method, this strategy effectively separates the production of LCEs and soft actuators. LCEs can be mass-produced in bulk by factories or producers and stored as prepared, much like rolls of cloth. When required, these LCEs can be customized into soft actuators as needed. This strategy provides a robust, flexible, and scalable solution to engineer soft actuators, holding great promise for mass production and universal applications.
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Affiliation(s)
- Huan Liang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yubai Zhang
- Research Institute of Petroleum Processing, Beijing, 100083, China
| | - Enjian He
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yang Yang
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, China
| | - Yawen Liu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hongtu Xu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Zhijun Yang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yixuan Wang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yen Wei
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
- Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung-Yuan Christian University, Chung-Li, Taiwan, 32023, China
| | - Yan Ji
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
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2
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Choi SH, Kim JH, Ahn J, Kim T, Jung Y, Won D, Bang J, Pyun KR, Jeong S, Kim H, Kim YG, Ko SH. Phase patterning of liquid crystal elastomers by laser-induced dynamic crosslinking. NATURE MATERIALS 2024; 23:834-843. [PMID: 38532072 DOI: 10.1038/s41563-024-01845-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 02/21/2024] [Indexed: 03/28/2024]
Abstract
Liquid crystal elastomers hold promise in various fields due to their reversible transition of mechanical and optical properties across distinct phases. However, the lack of local phase patterning techniques and irreversible phase programming has hindered their broad implementation. Here we introduce laser-induced dynamic crosslinking, which leverages the precision and control offered by laser technology to achieve high-resolution multilevel patterning and transmittance modulation. Incorporation of allyl sulfide groups enables adaptive liquid crystal elastomers that can be reconfigured into desired phases or complex patterns. Laser-induced dynamic crosslinking is compatible with existing processing methods and allows the generation of thermo- and strain-responsive patterns that include isotropic, polydomain and monodomain phases within a single liquid crystal elastomer film. We show temporary information encryption at body temperature, expanding the functionality of liquid crystal elastomer devices in wearable applications.
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Affiliation(s)
- Seok Hwan Choi
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Ju Hee Kim
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Jiyong Ahn
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Taegyeom Kim
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Yeongju Jung
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Daeyeon Won
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Junhyuk Bang
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Kyung Rok Pyun
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Seongmin Jeong
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Hyunsu Kim
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Young Gyu Kim
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea.
- Institute of Engineering Research / Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Seoul, Republic of Korea.
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, Korea.
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3
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Tian X, Guo Y, Zhang J, Ivasishin OM, Jia J, Yan J. Fiber Actuators Based on Reversible Thermal Responsive Liquid Crystal Elastomer. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2306952. [PMID: 38175860 DOI: 10.1002/smll.202306952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 12/16/2023] [Indexed: 01/06/2024]
Abstract
Soft actuators inspired by the movement of organisms have attracted extensive attention in the fields of soft robotics, electronic skin, artificial intelligence, and healthcare due to their excellent adaptability and operational safety. Liquid crystal elastomer fiber actuators (LCEFAs) are considered as one of the most promising soft actuators since they can provide reversible linear motion and are easily integrated or woven into complex structures to perform pre-programmed movements such as stretching, rotating, bending, and expanding. The research on LCEFAs mainly focuses on controllable preparation, structural design, and functional applications. This review, for the first time, provides a comprehensive and systematic review of recent advances in this important field by focusing on reversible thermal response LCEFAs. First, the thermal driving mechanism, and direct and indirect heating strategies of LCEFAs are systematically summarized and analyzed. Then, the fabrication methods and functional applications of LCEFAs are summarized and discussed. Finally, the challenges and technical difficulties that may hinder the performance improvement and large-scale production of LCEFAs are proposed, and the development opportunities of LCEFAs are prospected.
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Affiliation(s)
- Xuwang Tian
- College of Materials Science and Engineering, Key Laboratory of Automobile Materials Ministry of Education, Jilin University, Changchun, 130012, China
| | - Yongshi Guo
- College of Textile, Donghua University, Shanghai, 201620, China
| | - Jiaqi Zhang
- College of Materials Science and Engineering, Key Laboratory of Automobile Materials Ministry of Education, Jilin University, Changchun, 130012, China
| | - Orest M Ivasishin
- College of Materials Science and Engineering, Key Laboratory of Automobile Materials Ministry of Education, Jilin University, Changchun, 130012, China
| | - Jiru Jia
- School of Textile Garment and Design, Changshu Institute of Technology, Suzhou, Jiangsu, 215500, China
| | - Jianhua Yan
- College of Textile, Donghua University, Shanghai, 201620, China
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4
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Zhang J, Liu S, Wang X, Zhang X, Hu X, Zhang L, Sun Q, Liu X. 4D Printable liquid crystal elastomers with restricted nanointerfacial slippage for long-term-cyclic-stability photothermal actuation. MATERIALS HORIZONS 2024; 11:2483-2493. [PMID: 38477135 DOI: 10.1039/d3mh02230g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
Liquid crystal elastomers (LCEs) blended with photothermal nanofillers can reversibly and rapidly deform their shapes under external optical stimuli. However, nanointerfacial slipping inevitably occurs between the LCE molecules and the nanofillers due to their weak physical interactions, eventually resulting in cyclic instability. This work presents a versatile strategy to fabricate nanointerfacial-slipping-restricted photoactuation elastomers by chemically bonding the nanofillers into a thermally actuatable liquid crystal network. We experimentally and theoretically investigated three types of metal-based nanofillers, including zero-dimensional (0D) nanoparticles, one-dimensional (1D) nanowires, and two-dimensional (2D) nanosheets. The toughly crosslinked nanointerface allows for remarkably promoted interfacial thermal conductivity and stress transfer. Therefore, the resultant actuators enable the realization of long-term-cyclic-stability 4D-printed flexible intelligent systems such as the optical gripper, crawling robot, light-powered self-sustained windmill, butterflies with fluttering wings, and intelligent solar energy collection system.
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Affiliation(s)
- Juzhong Zhang
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Shuiren Liu
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Xianghong Wang
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Xiaomeng Zhang
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Xiaoguang Hu
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Linlin Zhang
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Qingqing Sun
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
| | - Xuying Liu
- School of Materials Science and Engineering, State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou 450001, China.
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5
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Fan Q, Tang Y, Sun H, Guo D, Ma J, Guo J. Cluster-Triggered Self-Luminescence, Rapid Self-Healing, and Adaptive Reprogramming Liquid Crystal Elastomers Enabled by Dynamic Imine Bond. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2401315. [PMID: 38627335 DOI: 10.1002/adma.202401315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 04/02/2024] [Indexed: 04/26/2024]
Abstract
The integration of advanced functions and diverse practical applications calls for multifunctional liquid crystal elastomers (LCEs); however, the structure-intrinsic luminescence and excellent mechanical properties of LCEs have not yet been explored. In this study, clusteroluminescence (CL)-based LCEs (CL-LCEs) are successfully fabricated without depending on large conjugated structures, thereby avoiding redundant organic synthesis and aggregation-caused quenching. The experimental and theoretical results reveal that secondary amine (-NH-) and imine (-C = N-) groups play vital roles in determining the presence of fluorescence in CL-LCEs. Based on the above observation, the strategy universalization and a molecular library for constructing CL-LCEs are further demonstrated. Meanwhile, the dynamic bond of imine bonds endows the CL-LCE system with rapid self-healing under mild conditions (70 °C in 10 min), excellent stretchability, and adaptive programmable characteristics. Furthermore, the self-luminescent performance enables visual detection of the self-healing process. Finally, CL-based information storage and anticounterfeiting are successfully realized and their applications in fiber actuators and fluorescent textiles are demonstrated. The distinctive luminescence and dynamic chemistry presented in this work has significant implications in elucidating the mechanism of CL and providing new strategies for the rational design of novel multifunctional LCE materials.
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Affiliation(s)
- Qingyan Fan
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yuting Tang
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Haonan Sun
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Dekang Guo
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Jiawei Ma
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Jinbao Guo
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
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6
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Nie ZZ, Wang M, Yang H. Self-sustainable autonomous soft actuators. Commun Chem 2024; 7:58. [PMID: 38503863 PMCID: PMC10951225 DOI: 10.1038/s42004-024-01142-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 03/07/2024] [Indexed: 03/21/2024] Open
Abstract
Self-sustainable autonomous locomotion is a non-equilibrium phenomenon and an advanced intelligence of soft-bodied organisms that exhibit the abilities of perception, feedback, decision-making, and self-sustainment. However, artificial self-sustaining architectures are often derived from algorithms and onboard modules of soft robots, resulting in complex fabrication, limited mobility, and low sensitivity. Self-sustainable autonomous soft actuators have emerged as naturally evolving systems that do not require human intervention. With shape-morphing materials integrating in their structural design, soft actuators can direct autonomous responses to complex environmental changes and achieve robust self-sustaining motions under sustained stimulation. This perspective article discusses the recent advances in self-sustainable autonomous soft actuators. Specifically, shape-morphing materials, motion characteristics, built-in negative feedback loops, and constant stimulus response patterns used in autonomous systems are summarized. Artificial self-sustaining autonomous concepts, modes, and deformation-induced functional applications of soft actuators are described. The current challenges and future opportunities for self-sustainable actuation systems are also discussed.
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Affiliation(s)
- Zhen-Zhou Nie
- School of Chemistry and Chemical Engineering, State Key Laboratory of Digital Medical Engineering, Institute of Advanced Materials, Southeast University, Nanjing, 211189, China
| | - Meng Wang
- School of Chemistry and Chemical Engineering, State Key Laboratory of Digital Medical Engineering, Institute of Advanced Materials, Southeast University, Nanjing, 211189, China
| | - Hong Yang
- School of Chemistry and Chemical Engineering, State Key Laboratory of Digital Medical Engineering, Institute of Advanced Materials, Southeast University, Nanjing, 211189, China.
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7
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Rešetič A. Shape programming of liquid crystal elastomers. Commun Chem 2024; 7:56. [PMID: 38485773 PMCID: PMC10940691 DOI: 10.1038/s42004-024-01141-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 03/07/2024] [Indexed: 03/18/2024] Open
Abstract
Liquid crystal elastomers (LCEs) are shape-morphing materials that demonstrate reversible actuation when exposed to external stimuli, such as light or heat. The actuation's complexity depends heavily on the instilled liquid crystal alignment, programmed into the material using various shape-programming processes. As an unavoidable part of LCE synthesis, these also introduce geometrical and output restrictions that dictate the final applicability. Considering LCE's future implementation in real-life applications, it is reasonable to explore these limiting factors. This review offers a brief overview of current shape-programming methods in relation to the challenges of employing LCEs as soft, shape-memory components in future devices.
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Affiliation(s)
- Andraž Rešetič
- Jožef Stefan Institute, Solid State Physics Department, Jamova cesta 39, 1000, Ljubljana, Slovenia.
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8
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Cooper EJ, Reynolds M, Raistrick T, Berrow SR, Jull EIL, Reshetnyak V, Mistry D, Gleeson HF. Controlling the Optical Properties of Transparent Auxetic Liquid Crystal Elastomers. Macromolecules 2024; 57:2030-2038. [PMID: 38495386 PMCID: PMC10938889 DOI: 10.1021/acs.macromol.3c02226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/16/2024] [Accepted: 01/30/2024] [Indexed: 03/19/2024]
Abstract
Determining the tunability of the optical coefficients, order parameter, and transition temperatures in optically transparent auxetic liquid crystal elastomers (LCEs) is vital for applications, including impact-resistant glass laminates. Here, we report measurements of the refractive indices, order parameters, and transition temperatures in a family of acrylate-based LCEs in which the mesogenic content varies from ∼50 to ∼85%. Modifications in the precursor mixture allow the order parameter, ⟨P2⟩, of the LCE to be adjusted from 0.46 to 0.73. The extraordinary refractive index changes most significantly with composition, from ∼1.66 to ∼1.69, in moving from a low to high mesogenic content. We demonstrate that all LCE refractive indices decrease with increasing temperature, with temperature coefficients of ∼10-4 K-1, comparable to optical plastics. In these LCEs, the average refractive index and the refractive index anisotropy are tunable via both chemical composition and order parameter control; we report design rules for both.
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Affiliation(s)
- Emily J. Cooper
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
| | - Matthew Reynolds
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
| | - Thomas Raistrick
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
| | - Stuart R. Berrow
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
| | - Ethan I. L. Jull
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
| | - Victor Reshetnyak
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
- Taras
Shevchenko National University of Kyiv, Kyiv 03680, Ukraine
| | - Devesh Mistry
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
| | - Helen F. Gleeson
- School
of Physics and Astronomy, University of
Leeds, Leeds LS2 9JT, United
Kingdom
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9
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Wan X, Xiao Z, Tian Y, Chen M, Liu F, Wang D, Liu Y, Bartolo PJDS, Yan C, Shi Y, Zhao RR, Qi HJ, Zhou K. Recent Advances in 4D Printing of Advanced Materials and Structures for Functional Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2312263. [PMID: 38439193 DOI: 10.1002/adma.202312263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 03/01/2024] [Indexed: 03/06/2024]
Abstract
4D printing has attracted tremendous worldwide attention during the past decade. This technology enables the shape, property, or functionality of printed structures to change with time in response to diverse external stimuli, making the original static structures alive. The revolutionary 4D-printing technology offers remarkable benefits in controlling geometric and functional reconfiguration, thereby showcasing immense potential across diverse fields, including biomedical engineering, electronics, robotics, and photonics. Here, a comprehensive review of the latest achievements in 4D printing using various types of materials and different additive manufacturing techniques is presented. The state-of-the-art strategies implemented in harnessing various 4D-printed structures are highlighted, which involve materials design, stimuli, functionalities, and applications. The machine learning approach explored for 4D printing is also discussed. Finally, the perspectives on the current challenges and future trends toward further development in 4D printing are summarized.
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Affiliation(s)
- Xue Wan
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Zhongmin Xiao
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Yujia Tian
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Mei Chen
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- HP-NTU Digital Manufacturing Corporate Lab, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Feng Liu
- State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083, China
| | - Dong Wang
- School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yong Liu
- State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083, China
| | - Paulo Jorge Da Silva Bartolo
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Chunze Yan
- State Key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yusheng Shi
- State Key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Ruike Renee Zhao
- Department of Mechanical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Hang Jerry Qi
- School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Kun Zhou
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- HP-NTU Digital Manufacturing Corporate Lab, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
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10
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Feng W, He Q, Zhang L. Embedded Physical Intelligence in Liquid Crystalline Polymer Actuators and Robots. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2312313. [PMID: 38375751 DOI: 10.1002/adma.202312313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/27/2024] [Indexed: 02/21/2024]
Abstract
Responsive materials possess the inherent capacity to autonomously sense and respond to various external stimuli, demonstrating physical intelligence. Among the diverse array of responsive materials, liquid crystalline polymers (LCPs) stand out for their remarkable reversible stimuli-responsive shape-morphing properties and their potential for creating soft robots. While numerous reviews have extensively detailed the progress in developing LCP-based actuators and robots, there exists a need for comprehensive summaries that elucidate the underlying principles governing actuation and how physical intelligence is embedded within these systems. This review provides a comprehensive overview of recent advancements in developing actuators and robots endowed with physical intelligence using LCPs. This review is structured around the stimulus conditions and categorizes the studies involving responsive LCPs based on the fundamental control and stimulation logic and approach. Specifically, three main categories are examined: systems that respond to changing stimuli, those operating under constant stimuli, and those equip with learning and logic control capabilities. Furthermore, the persisting challenges that need to be addressed are outlined and discuss the future avenues of research in this dynamic field.
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Affiliation(s)
- Wei Feng
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Qiguang He
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Li Zhang
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Hong Kong, China
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11
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Ma S, Zhou Y, Wang L, Zhang H. Multifunctional UV-NIR Dual Light-Responsive Soft Actuators from a Main-Chain Azobenzene Semi-Crystalline Poly(ester-amide) Doped with Polydopamine Nanoparticles. Chemistry 2024; 30:e202303306. [PMID: 37965800 DOI: 10.1002/chem.202303306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/14/2023] [Accepted: 11/14/2023] [Indexed: 11/16/2023]
Abstract
The development of soft photoactuators with multifunctionality and improved performance is highly important for their broad applications. Herein, we report on a facile and efficient strategy for fabricating such photoactuators with UV-NIR dual light-responsivity, room-temperature 3D shape reprogrammability and reprocessability, and photothermal healability by doping polydopamine (PDA) nanoparticles into a main-chain azobenzene semi-crystalline poly(ester-amide) (PEA). The PEA/PDA nanoparticle composite was readily processed into free-standing films with enhanced mechanical and photomechanical properties compared with the blank PEA films. Its physically crosslinked uniaxially oriented films showed rapid and highly reversible photochemically induced bending/unbending under the UV/visible light irradiation at room temperature in both the air atmosphere and water. When exposed to the NIR light, they (and their bilayer films formed with a polyimide film) exhibited photothermally induced bending even at a temperature much lower than their crystalline-to-isotropic phase transition temperature based on a unique mechanism (involving photothermally induced polymer chain relaxation due to the disruption of their hydrogen bonds). The room-temperature 3D shape reprogrammability and reprocessability and photothermal healability of the composite polymer films were also demonstrated. Such multifunctional dual light-responsive photoactuators with well-balanced mechanical robustness, actuation stability, 3D shape reprogrammability/reprocessability and photothermal healability hold much promise in various photoactuating applications.
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Affiliation(s)
- Shengkui Ma
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Tianjin Key Laboratory of Functional Polymer Materials, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Yan Zhou
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Tianjin Key Laboratory of Functional Polymer Materials, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Lei Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Tianjin Key Laboratory of Functional Polymer Materials, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Huiqi Zhang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Tianjin Key Laboratory of Functional Polymer Materials, College of Chemistry, Nankai University, Tianjin, 300071, China
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12
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Zhang C, Fei G, Lu X, Xia H, Zhao Y. Liquid Crystal Elastomer Artificial Tendrils with Asymmetric Core-Sheath Structure Showing Evolutionary Biomimetic Locomotion. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2307210. [PMID: 37805917 DOI: 10.1002/adma.202307210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/05/2023] [Indexed: 10/09/2023]
Abstract
The sophisticated and complex haptonastic movements in response to environmental-stimuli of living organisms have always fascinated scientists. However, how to fundamentally mimic the sophisticated hierarchical architectures of living organisms to provide the artificial counterparts with similar or even beyond-natural functions based on the underlying mechanism remains a major scientific challenge. Here, liquid crystal elastomer (LCE) artificial tendrils showing evolutionary biomimetic locomotion are developed following the structure-function principle that is used in nature to grow climbing plants. These elaborately designed tendril-like LCE actuators possess an asymmetric core-sheath architecture which shows a higher-to-lower transition in the degree of LC orientation from the sheath-to-core layer across the semi-ellipse cross-section. Upon heating and cooling, the LCE artificial tendril can undergo reversible tendril-like shape-morphing behaviors, such as helical coiling/winding, and perversion. The fundamental mechanism of the helical shape-morphing of the artificial tendril is revealed by using theoretical models and finite element simulations. Besides, the incorporation of metal-ligand coordination into the LCE network provides the artificial tendril with reconfigurable shape-morphing performances such as helical transitions and rotational deformations. Finally, the abilities of helical and rotational deformations are integrated into a new reprogrammed flagellum-like architecture to perform evolutionary locomotion mimicking the haptonastic movements of the natural flagellum.
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Affiliation(s)
- Chun Zhang
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu, 610065, China
| | - Guoxia Fei
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu, 610065, China
| | - Xili Lu
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu, 610065, China
| | - Hesheng Xia
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu, 610065, China
| | - Yue Zhao
- Département de chimie Université de Sherbrooke Sherbrooke, Québec, J1K 2R1, Canada
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13
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Jeong YJ, Park SY. Light-Responsive Actuator of Azobenzene-Containing Main-Chain Liquid Crystal Elastomers with Allyl Sulfide Dynamic Exchangeable Linkages. ACS APPLIED MATERIALS & INTERFACES 2024; 16:2788-2801. [PMID: 38170866 DOI: 10.1021/acsami.3c17068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Herein, a light-responsive and light-induced bond-exchange-reaction (BER)-capable actuator of the monodomain liquid crystal elastomer (xMLCEazo), developed using main-chain mesogenic oligomers containing azobenzene and allyl sulfide linkages, is investigated. Large quantities of the azobenzene and allyl dithiol linkages are incorporated into the main-chain mesogenic oligomer prepared via thiol-acrylate Michael addition polymerization (TAMAP). The xMLCEazo film is generated via visible-light-induced BER of the drawn polydomain xLCEazo (xPLCEazo) film prepared via TAMAP of tetrathiol cross-linkers and diacrylate-terminated mesogenic oligomers. The xMLCEazo film exhibits large length actuation (38%) through the photothermal effect, along with excellent self-healing and reprogramming properties, under ultraviolet (UV) light irradiation. UV light induced BER of the xMLCEazo film is used to develop complex-shaped actuators with a bilayer film, containing the xMLCEazo and xPLCEazo films, which are bonded by the UV light induced BER without glue. The individual arm of the complex eight-arm flower is remotely actuated under UV light irradiation, and a circular band is rolled under blue laser light irradiation, demonstrating the local remote-controlled actuation and fuel-free motion of the motile soft robot using light irradiation, respectively. Thus, the xMLCEazo film can be expanded to other interesting applications requiring reprogrammable, self-healing, reprocessable, patternable, and remote-controlled light-triggered elastic, rubber-like actuators.
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Affiliation(s)
- You-Jeong Jeong
- Department of Polymer Science and Engineering, Polymeric Nano Materials Laboratory, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Soo-Young Park
- Department of Polymer Science and Engineering, Polymeric Nano Materials Laboratory, Kyungpook National University, Daegu 41566, Republic of Korea
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14
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Li S, Aizenberg M, Lerch MM, Aizenberg J. Programming Deformations of 3D Microstructures: Opportunities Enabled by Magnetic Alignment of Liquid Crystalline Elastomers. ACCOUNTS OF MATERIALS RESEARCH 2023; 4:1008-1019. [PMID: 38148997 PMCID: PMC10749463 DOI: 10.1021/accountsmr.3c00101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 09/10/2023] [Indexed: 12/28/2023]
Abstract
Synthetic structures that undergo controlled movement are crucial building blocks for developing new technologies applicable to robotics, healthcare, and sustainable self-regulated materials. Yet, programming motion is nontrivial, and particularly at the microscale it remains a fundamental challenge. At the macroscale, movement can be controlled by conventional electric, pneumatic, or combustion-based machinery. At the nanoscale, chemistry has taken strides in enabling molecularly fueled movement. Yet in between, at the microscale, top-down fabrication becomes cumbersome and expensive, while bottom-up chemical self-assembly and amplified molecular motion does not reach the necessary sophistication. Hence, new approaches that converge top-down and bottom-up methods and enable motional complexity at the microscale are urgently needed. Synthetic anisotropic materials (e.g., liquid crystalline elastomers, LCEs) with encoded molecular anisotropy that are shaped into arbitrary geometries by top-down fabrication promise new opportunities to implement controlled actuation at the microscale. In such materials, motional complexity is directly linked to the built-in molecular anisotropy that can be "activated" by external stimuli. So far, encoding the desired patterns of molecular directionality has relied mostly on either mechanical or surface alignment techniques, which do not allow the decoupling of molecular and geometric features, severely restricting achievable material shapes and thus limiting attainable actuation patterns, unless complex multimaterial constructs are fabricated. Electromagnetic fields have recently emerged as possible alternatives to provide 3D control over local anisotropy, independent of the geometry of a given 3D object. The combination of magnetic alignment and soft lithography, in particular, provides a powerful platform for the rapid, practical, and facile production of microscale soft actuators with field-defined local anisotropy. Recent work has established the feasibility of this approach with low magnetic field strengths (in the lower mT range) and comparably simple setups used for the fabrication of the microactuators, in which magnetic fields can be engineered through arrangement of permanent magnets. This workflow gives access to microstructures with unusual spatial patterning of molecular alignment and has enabled a multitude of nontrivial deformation types that would not be possible to program by any other means at the micron scale. A range of "activating" stimuli can be used to put these structures in motion, and the type of the trigger plays a key role too: directional and dynamic stimuli (such as light) make it possible to activate the patterned anisotropic material locally and transiently, which enables one to achieve and further program motional complexity and communication in microactuators. In this Account, we will discuss recent advances in magnetic alignment of molecular anisotropy and its use in soft lithography and related fabrication approaches to create LCE microactuators. We will examine how design choices-from the molecular to the fabrication and the operational levels-control and define the achievable LCE deformations. We then address the role of stimuli in realizing the motional complexity and how one can engineer feedback within and communication between microactuator arrays fabricated by soft lithography. Overall, we outline emerging strategies that make possible a completely new approach to designing for desired sets of motions of active, microscale objects.
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Affiliation(s)
- Shucong Li
- Department
of Chemistry and Chemical Biology, Harvard
University, Cambridge, Massachusetts 02138, United States
- Department
of Mechanical Engineering, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Michael Aizenberg
- John
A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Michael M. Lerch
- John
A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
- Stratingh
Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Joanna Aizenberg
- Department
of Chemistry and Chemical Biology, Harvard
University, Cambridge, Massachusetts 02138, United States
- John
A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
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15
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Saeed MH, Choi MY, Kim K, Lee JH, Kim K, Kim D, Kim SU, Kim H, Ahn SK, Lan R, Na JH. Electrostatically Powered Multimode Liquid Crystalline Elastomer Actuators. ACS APPLIED MATERIALS & INTERFACES 2023; 15:56285-56292. [PMID: 37991738 DOI: 10.1021/acsami.3c13140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Soft actuators based on liquid crystalline elastomers (LCEs) are captivating significant interest because of their unique properties combining the programmable liquid crystalline molecular order and elasticity of polymeric materials. For practical applications, the ability to perform multimodal shape changes in a single LCE actuator at a subsecond level is a bottleneck. Here, we fabricate a monodomain LCE powered by electrostatic force, which enables fast multidirectional bending, oscillation, rotation, and complex actuation with a high degree of freedom. By tuning the dielectric constant and resistivity in LCE gels, a complete cycle of oscillation and rotation only takes 0.1 s. In addition, monodomain actuators exhibit anisotropic actuation behaviors that promise a more complex deployment in a potential electromechanical system. The presented study will pave the way for electrostatically controllable isothermal manipulation for a fast and multimode soft actuator.
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Affiliation(s)
- Mohsin Hassan Saeed
- Department of Electrical, Electronics and Communication Engineering Education, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Moon-Young Choi
- Department of Convergence System Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Kitae Kim
- Department of Convergence System Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jin-Hyeong Lee
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Keumbee Kim
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Dowon Kim
- Department of Electrical, Electronics and Communication Engineering Education, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Se-Um Kim
- Department of Electrical and Information Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea
| | - Hyun Kim
- Advanced Materials Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Suk-Kyun Ahn
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
- Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Ruochen Lan
- Institute of Advanced Materials, Jiangxi Normal University, Nanchang 330022, China
| | - Jun-Hee Na
- Department of Electrical, Electronics and Communication Engineering Education, Chungnam National University, Daejeon 34134, Republic of Korea
- Department of Convergence System Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
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16
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Jin B, Zhu Z, Wong TW, Chen G. Network Topology Optimization for Alignment Programming of a Dynamic Liquid Crystalline Organo-Gel. ACS Macro Lett 2023; 12:1486-1490. [PMID: 37874195 DOI: 10.1021/acsmacrolett.3c00512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Liquid crystalline elastomers (LCEs) exhibit muscle-like actuation upon an external stimulus. To control this, various alignment programming strategies have been developed over the past decades. Among them, force-directed solvent evaporation, namely, that the alignment depends on the applied external force during solvent evaporation, is appreciated for its universality in material design and versatility in attainable actuations. Here, we investigate the influence of network topology on the alignment programming of a liquid crystalline (LC) organo-gel via varying feeding ratios of the monomers. As a result, distinct self-supporting actuations can be repeatedly introduced into a topology-optimized LC organo-gel. Beyond this, the bond exchange reaction of the embedded ester groups can be activated upon heating, which enables alignment manipulation based on dynamic network reconfiguration after drying. The availability of inviting two distinct programming strategies into one LCE network allows us to regulate the LCE alignment at both the gel and dried states, offering ample room to diversify actuation manners. Our design principle shall be adopted by other dynamic LCE systems owing to its maneuverability.
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Affiliation(s)
- Binjie Jin
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Zhan Zhu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Tuck-Whye Wong
- Membrane Technology Research Centre, School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia
| | - Guancong Chen
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, Zhejiang, China
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17
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Wu X, Yuan Y, Zhao S, Lei Y, Fu X, Lei J, Jiang L. The Synergistic Effects between Liquid Crystal and Crystalline Phase on Photo-Responsive Elastomers toward Quick Photo-Responsive Performance. Macromol Rapid Commun 2023; 44:e2300354. [PMID: 37572076 DOI: 10.1002/marc.202300354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/05/2023] [Indexed: 08/14/2023]
Abstract
Adopting only a small amount of azobenzene molecular to design liquid crystal photo-responsive materials capable of quick response and flexible adjustability is in high demand but is challenging. Herein, azobenzenemolecules into polyurethane elastomer containing crystalline structure for preparing azobenzene liquid-crystal elastomers (ALCEs) are demonstrated and this phenomenon of the synergistic effects between liquid crystal and crystalline phase is discovered. The key point of the work is that the synthetic ALCEs can utilize the reversible isomerism capability of azobenzene molecules under light irradiation, which can pry the motion of the macromolecular crystalline region in system to realize the large macroscopic deformation of the photo-responsive behavior. Obviously, the ALCEs sample containing azobenzene molecule and polyethylene glycol crystallization can quickly bend, illuminated by ultraviolet light and rapidly straighten under green light. Under the same ultraviolet irradiation, the bending speed, final bending angle, recovery rate and recovery ratio of ALCEs are larger than that of ALCEs without any crystalline structure. This ALCEs based on the synergistic effects between liquid crystal and crystalline phase can break through the current dilemma that the application of traditional azobenzene photo-responsive materials is limited by their concentration, greatly expanding the design thought and their scope of application.
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Affiliation(s)
- Xudong Wu
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
| | - Ye Yuan
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
- Scientific Research Institute, Luzhou North Chemistry Industry Corporation, Luzhou, 646100, P. R. China
| | - Shiwei Zhao
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
| | - Yuan Lei
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
| | - Xiaowei Fu
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
| | - Jingxin Lei
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
| | - Liang Jiang
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, P. R. China
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18
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Guo H, Liang C, Ruoko TP, Meteling H, Peng B, Zeng H, Priimagi A. Programmable and Self-Healable Liquid Crystal Elastomer Actuators Based on Halogen Bonding. Angew Chem Int Ed Engl 2023; 62:e202309402. [PMID: 37694550 DOI: 10.1002/anie.202309402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/12/2023]
Abstract
Shape-changing polymeric materials have gained significant attention in the field of bioinspired soft robotics. However, challenges remain in versatilizing the shape-morphing process to suit different tasks and environments, and in designing systems that combine reversible actuation and self-healing ability. Here, we report halogen-bonded liquid crystal elastomers (LCEs) that can be arbitrarily shape-programmed and that self-heal under mild thermal or photothermal stimulation. We incorporate halogen-bond-donating diiodotetrafluorobenzene molecules as dynamic supramolecular crosslinks into the LCEs and show that these relatively weak crosslinks are pertinent for their mechanical programming and self-healing. Utilizing the halogen-bonded LCEs, we demonstrate proof-of-concept soft robotic motions such as crawling and rolling with programmed velocities. Our results showcase halogen bonding as a promising, yet unexplored tool for the preparation of smart supramolecular constructs for the development of advanced soft actuators.
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Affiliation(s)
- Hongshuang Guo
- Faculty of Engineering and Natural Sciences, Tampere University P.O. Box 541, 33101, Tampere, Finland
| | - Chen Liang
- Department of Applied Physics, Aalto University P.O. Box 15100, 02150, Espoo, Finland
| | - Tero-Petri Ruoko
- Faculty of Engineering and Natural Sciences, Tampere University P.O. Box 541, 33101, Tampere, Finland
| | - Henning Meteling
- Faculty of Engineering and Natural Sciences, Tampere University P.O. Box 541, 33101, Tampere, Finland
| | - Bo Peng
- Department of Applied Physics, Aalto University P.O. Box 15100, 02150, Espoo, Finland
| | - Hao Zeng
- Faculty of Engineering and Natural Sciences, Tampere University P.O. Box 541, 33101, Tampere, Finland
| | - Arri Priimagi
- Faculty of Engineering and Natural Sciences, Tampere University P.O. Box 541, 33101, Tampere, Finland
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19
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Dong C, Yue X, Zhang Y, Wang Y, Ren ZH, Guan ZH. Synthesis of Self-healing and Light-, Thermal-, and Humidity-induced Deformative Polyurethane Actuator. Macromol Rapid Commun 2023; 44:e2300281. [PMID: 37543181 DOI: 10.1002/marc.202300281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/19/2023] [Indexed: 08/07/2023]
Abstract
Intelligent actuating materials have drawn enormous attention because of their potential applications in soft robots, smart sensors, bionics, etc. Aiming to integrate light, thermal, and humidity stimuli deformations and self-healing function into a single polymer, a smart actuating polyurethane material CPPU-50 is designed and successfully synthesized through co-polymerization of azobenzene-containing Azo-C12 , polyethylene glycol 200 (PEG200), and 4,4'-diphenylmethane diisocyanate (MDI) at a ratio of 1:1:2. The obtained polyurethane CPPU-50 exhibits good photoinduced bending, thermal responsive shape memory effect, humidity triggered deflections and self-healing properties. Furthermore, an actuator combining light and thermal stimuli is created and the self-healing CPPU-50 film can withstand the object of 1800 times without tearing. This work can pave a way for further development of long-lived multi-stimuli-responsive actuating devices and intelligent materials.
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Affiliation(s)
- Chen Dong
- Key Laboratory of Synthetic and Nature Molecule of Ministry of Education, Shaanxi Key Laboratory for Carbon Neutral Technology, Department of Chemistry & Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Xiaolei Yue
- Key Laboratory of Synthetic and Nature Molecule of Ministry of Education, Shaanxi Key Laboratory for Carbon Neutral Technology, Department of Chemistry & Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Yaodu Zhang
- Key Laboratory of Synthetic and Nature Molecule of Ministry of Education, Shaanxi Key Laboratory for Carbon Neutral Technology, Department of Chemistry & Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Yucheng Wang
- Key Laboratory of Synthetic and Nature Molecule of Ministry of Education, Shaanxi Key Laboratory for Carbon Neutral Technology, Department of Chemistry & Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Zhi-Hui Ren
- Key Laboratory of Synthetic and Nature Molecule of Ministry of Education, Shaanxi Key Laboratory for Carbon Neutral Technology, Department of Chemistry & Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Zheng-Hui Guan
- Key Laboratory of Synthetic and Nature Molecule of Ministry of Education, Shaanxi Key Laboratory for Carbon Neutral Technology, Department of Chemistry & Materials Science, Northwest University, Xi'an, 710127, P. R. China
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20
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Fan Y, Liu T, Li Y, Miao X, Chen B, Ding J, Dong Z, Rios O, Bao B, Lin Q, Zhu L. One-Step Manufacturing of Supramolecular Liquid-Crystal Elastomers by Stress-Induced Alignment and Hydrogen Bond Exchange. Angew Chem Int Ed Engl 2023; 62:e202308793. [PMID: 37496468 DOI: 10.1002/anie.202308793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 07/18/2023] [Accepted: 07/26/2023] [Indexed: 07/28/2023]
Abstract
Liquid-crystal elastomers (LCEs) capable of performing large and reversible deformation in response to an external stimulus are an important class of soft actuators. However, their manufacturing process typically involves a multistep approach that requires harsh conditions. For the very first time, LCEs with customized geometries that can be manufactured by a rapid one-step approach at room temperature are developed. The LCEs are hydrogen bond (H-bond) crosslinked main chain polymers comprising flexible short side chains. Applying a stretching/shear force to the LCE can simultaneously induce mesogen alignment and H-bond exchange, allowing for the formation of well-aligned LCE networks stabilized by H-bonds. Based on this working principle, soft actuators in fibers and 2D/3D objects can be manufactured by mechanical stretching or melt extrusion within a short time (e.g. <1 min). These actuators can perform reversible macroscopic motions with large, controlled deformations up to 38 %. The dynamic nature of H-bonds also provides the actuators with reprocessability and reprogrammability. Thus, this work opens the way for the one-step and custom manufacturing of soft actuators.
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Affiliation(s)
- Yuexin Fan
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Tuan Liu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Yuzhan Li
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Xuepei Miao
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, Changzhou, 213032, P. R. China
| | - Baihang Chen
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Jian Ding
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Zhixiang Dong
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Orlando Rios
- Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Bingkun Bao
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Qiuning Lin
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Linyong Zhu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
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21
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Zhang Z, Yang X, Zhao Y, Ye F, Shang L. Liquid Crystal Materials for Biomedical Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2300220. [PMID: 37235719 DOI: 10.1002/adma.202300220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 04/04/2023] [Indexed: 05/28/2023]
Abstract
Liquid crystal is a state of matter being intermediate between solid and liquid. Liquid crystal materials exhibit both orientational order and fluidity. While liquid crystals have long been highly recognized in the display industry, in recent decades, liquid crystals provide new opportunities into the cross-field of material science and biomedicine due to their biocompatibility, multifunctionality, and responsiveness. In this review, the latest achievements of liquid crystal materials applied in biomedical fields are summarized. The start is made by introducing the basic concepts of liquid crystals, and then shifting to the components of liquid crystals as well as functional materials derived therefrom. After that, the ongoing and foreseeable applications of liquid crystal materials in the biomedical field with emphasis put on several cutting-edge aspects, including drug delivery, bioimaging, tissue engineering, implantable devices, biosensing, and wearable devices are discussed. It is hoped that this review will stimulate ingenious ideas for the future generation of liquid crystal-based drug development, artificial implants, disease diagnosis, health status monitoring, and beyond.
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Affiliation(s)
- Zhuohao Zhang
- Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Xinyuan Yang
- Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Yuanjin Zhao
- Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
- Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, School of Biological Science and Medical Engineering Southeast University, Nanjing, 210096, China
| | - Fangfu Ye
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang, 325001, China
| | - Luoran Shang
- Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
- Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, School of Biological Science and Medical Engineering Southeast University, Nanjing, 210096, China
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22
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Sun J, Liao W, Yang Z. Additive Manufacturing of Liquid Crystal Elastomer Actuators Based on Knitting Technology. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2302706. [PMID: 37278691 DOI: 10.1002/adma.202302706] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/12/2023] [Indexed: 06/07/2023]
Abstract
Liquid crystal elastomer (LCE) exhibits large and reversible deformability originating from the alignment of liquid crystal mesogens. Additive manufacturing provides high controllability in the alignment and shaping process of LCE actuators. However, it still remains a challenge to customize LCE actuators with both diverse 3D deformability and recyclability. In this study, a new strategy is developed to exploit knitting technique to additively manufacture LCE actuators. The obtained LCE actuators are fabric-structured with designed geometry and deformability. By accurately adjusting the parameters of the knitting patterns as modules, diverse geometry is pixel-wise designed, and complex 3D deformations including bending, twisting, and folding are quantitatively controlled. In addition, the fabric-structured LCE actuators can be threaded, stitched, and reknitted to achieve advanced geometry, integrated multi-functions and efficient recyclability. This approach allows the fabrication of versatile LCE actuators with potential applications in smart textiles and soft robots.
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Affiliation(s)
- Jiahao Sun
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Wei Liao
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Zhongqiang Yang
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
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23
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Zhao J, Meng F. Modeling Viscoelasticity and Dynamic Nematic Order of Exchangeable Liquid Crystal Elastomers. PHYSICAL REVIEW LETTERS 2023; 131:068101. [PMID: 37625059 DOI: 10.1103/physrevlett.131.068101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Accepted: 04/26/2023] [Indexed: 08/27/2023]
Abstract
Exchangeable liquid crystal elastomers (XLCEs), an emerging class of recyclable polymer materials, consist of liquid crystalline polymers which are dynamically crosslinked. We develop a macroscopic continuum model by incorporating the microscopic dynamic features of the cross-links, which can be utilized to understand the viscoelasticity of the materials together with the dynamic nematic order. As applications of the model, we study the rheological responses of XLCEs in three cases: stress relaxation, strain ramp, and creep compliance, where the materials show interesting rheology as an interplay between the dynamic nematic order of the mesogenic units, the elasticity from the network structure, and the dissipation due to chain exchange reactions. Not only being useful in understanding the physical mechanism underlying the fascinating characteristics of XLCEs, this work can also guide their future fabrications with desired rheological properties.
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Affiliation(s)
- Jiameng Zhao
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fanlong Meng
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325000, China
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24
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Zhang X, Liao W, Wang Y, Yang Z. Thermal-Responsive Liquid Crystal Elastomer Foam-based Compressible and Omnidirectional Gripper. Chem Asian J 2023; 18:e202300340. [PMID: 37325932 DOI: 10.1002/asia.202300340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/13/2023] [Accepted: 06/15/2023] [Indexed: 06/17/2023]
Abstract
Liquid crystal elastomers (LCEs) are considered to be a promising material for the fabrication of soft grippers because of their large and reversible deformations, an LCE gripper with suitable compressibility and omnidirectionality has not yet been developed. To overcome these obstacles, this study utilizes salt template method to fabricate a rod-like LCE foam as gripper. The thickness of the compressible foam can be reduced by up to 77%, temporarily maintaining the deformation and enabling the gripper to pass through slits. The foam was aligned along the long axis and the length of the foam exhibits reversible thermal responsiveness and contract up to 57% along its alignment. Additionally, when the foam approaches a heat source, the generated temperature gradient results in a contraction gradient owing to the low thermal conductivity of the LCE foam. This in turn causes the foam to reversibly bend with a bending angle up to 93° and follow the movement of a heat source omnidirectionally. The developed gripper successfully grasps, moves, and releases hot objects in a cold and safe place, demonstrating its potential for emergency disposal. Thus, LCE foams can be considered suitable materials for novel gripper design and construction.
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Affiliation(s)
- Xinyuhang Zhang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, 100084, Beijing, P. R. China
| | - Wei Liao
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, 100084, Beijing, P. R. China
| | - Yunpeng Wang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, 100084, Beijing, P. R. China
| | - Zhongqiang Yang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, 100084, Beijing, P. R. China
- Laboratory of Flexible Electronics Technology, Tsinghua University, 100084, Beijing, P. R. China
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25
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Yao Y, He E, Xu H, Liu Y, Yang Z, Wei Y, Ji Y. Enabling liquid crystal elastomers with tunable actuation temperature. Nat Commun 2023; 14:3518. [PMID: 37316483 DOI: 10.1038/s41467-023-39238-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 05/31/2023] [Indexed: 06/16/2023] Open
Abstract
Liquid crystalline elastomers are regarded as a kind of desirable soft actuator material for soft robotics and other high-tech areas. The isotropization temperature (Ti) plays an important role as it determines the actuation temperature and other properties, which in turn has a great effect on their applications. In the past, the common physical methods (e.g. annealing) to tune Ti is not applicable to tune the actuation temperature. The new Ti obtained by annealing immediately goes back to the old one once it is heated to a temperature above Ti, while actuation needs a temperature higher than Ti. For a fully cross-linked LCE material, once it is synthesized, the actuation temperature is fixed. Accordingly, the actuation temperature can not be tuned unless the chemical structure is changed, which usually needs to start from the very beginning of the molecular design and material synthesis. Here, we found that different Ti achieved by annealing can be preserved by reversible reactions of dynamic covalent bonds in covalently adaptable LC networks including LC vitrimers. Thus, a variety of soft actuators with different actuation temperatures can be obtained from the same fully cross-linked LCE material. As the tuning of Ti is also reversible, the same actuator can be adjusted for applications with different actuation temperature requirements. Such tuning will also expand the application of LCEs.
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Affiliation(s)
- Yanjin Yao
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Enjian He
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hongtu Xu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yawen Liu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Zhijun Yang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yen Wei
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
- Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung-Yuan Christian University, Chung-Li, 32023, Taiwan, China
| | - Yan Ji
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China.
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26
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Ma S, Wang L, Zhou Y, Zhang H. Fully Room Temperature Reprogrammable, Recyclable, and Photomobile Soft Actuators from Physically Cross-Linked Main-Chain Azobenzene Liquid Crystalline Polymers. Molecules 2023; 28:molecules28104174. [PMID: 37241914 DOI: 10.3390/molecules28104174] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/14/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Fully room temperature three-dimensional (3D) shape-reprogrammable, recyclable, and photomobile azobenzene (azo) polymer actuators hold much promise in many photoactuating applications, but their development is challenging. Herein, we report on the efficient synthesis of a series of main-chain azo liquid crystalline polymers (LCPs) with such performances via Michael addition polymerization. They have both ester groups and two kinds of hydrogen bond-forming groups (i.e., amide and secondary amino groups) and different flexible spacer length in the backbones. Such poly(ester-amide-secondary amine)s (PEAsAs) show low glass transition temperatures (Tg ≤ 18.4 °C), highly ordered smectic liquid crystalline phases, and reversible photoresponsivity. Their uniaxially oriented fibers fabricated via the melt spinning method exhibit good mechanical strength and photoinduced reversible bending/unbending and large stress at room temperature, which are largely influenced by the flexible spacer length of the polymers. Importantly, all these fibers can be easily reprogrammed under strain at 25 °C into stable fiber springs capable of showing a totally different photomobile mode (i.e., unwinding/winding), mainly owing to the presence of low Tg and both dynamic hydrogen bonding and stable crystalline domains (induced by the uniaxial drawing during the fiber formation). They can also be recycled from a solution at 25 °C. This work not only presents the first azo LCPs with 3D shape reprogrammability, recyclability, and photomobility at room temperature, but also provides some important knowledge of their structure-property relationship, which is useful for designing more advanced photodeformable azo polymers.
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Affiliation(s)
- Shengkui Ma
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
| | - Lei Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yan Zhou
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
| | - Huiqi Zhang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
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27
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Yao Y, He E, Xu H, Liu Y, Wei Y, Ji Y. Fabricating liquid crystal vitrimer actuators far below the normal processing temperature. MATERIALS HORIZONS 2023; 10:1795-1805. [PMID: 36857698 DOI: 10.1039/d3mh00184a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Liquid crystal vitrimers can be reprocessed, reshaped, welded, and healed due to exchange-reaction-enabled topology changes despite having fully covalently cross-linked network structures. Fabricating liquid crystal (LC) vitrimer actuators is invariably carried out above a characteristic temperature known as the topology freezing transition temperature (Tv). The reason that all exchange-reaction-based operations must be performed above Tv is because the exchange reaction is insignificant below Tv. Here we find that LC vitrimers can be reshaped at temperatures below the measured Tv, whereas non-LC vitrimers cannot. The work here not only makes it possible to create reprogrammable and stable LC vitrimer actuators at low temperatures but also reminds us that both our measurement and understanding of the Tv need further attention to facilitate the use of vitrimers in different areas.
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Affiliation(s)
- Yanjin Yao
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, China.
| | - Enjian He
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, China.
| | - Hongtu Xu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, China.
| | - Yawen Liu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, China.
| | - Yen Wei
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, China.
- Chung-Yuan Christian University, Chung-Li, 32023, Taiwan, China
| | - Yan Ji
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, China.
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28
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Zheng X, Ma Q, Tao Y, Huang Y, Li M, Ji H. Ultrasonic-Excited Ultrafast Seamless Integration of Heterostructured Liquid Crystalline Elastomers for Multi-responsive Soft Actuators. ACS APPLIED MATERIALS & INTERFACES 2023; 15:13609-13617. [PMID: 36857738 DOI: 10.1021/acsami.2c21888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Multicomponent/heterostructured liquid crystalline elastomers (LCEs) have recently garnered extensive attention for the design of soft robots with high dexterity and flexibility. However, the reported integration strategies of LCEs seriously suffer from high welding temperature, long processing time, and poor joint quality. Herein, the high-efficiency seamless ultrasonic welding (UW) of reprogrammable silver nanowire-LCE composites (AgNW-LCEs) have been realized without any auxiliary reagents based on the dynamic silver-disulfide coordination interactions. The elaborate combination of silver-disulfide coordination interactions and UW technology establishes an effective double-network welding mechanism of AgNWs and dynamic LC networks due to the high-frequency vibration at the welding interface. During the UW process, monolithic AgNW-LCEs can be integrated into heterostructured actuators at room temperature for 0.68 s. Furthermore, the welded AgNW-LCEs demonstrate an exceptional strain healing efficiency of ∼100%, a stress healing efficiency of ∼85%, and a maintained orientation of the LC alignment. Taking advantage of the high-efficiency UW technology, the heterostructured AgNW-LCE actuators with different LC alignments or LC monomers have been successfully implemented for a multi-degree-of-freedom soft robotic arm and a time-modulated flower-mimic actuator. This work provides an efficient approach toward the development of multi-responsive entirely soft actuators based on smart polymers.
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Affiliation(s)
- Xiaoxiong Zheng
- The State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
- Sauvage Laboratory for Smart Materials, Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
| | - Qiuchen Ma
- The State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
- Sauvage Laboratory for Smart Materials, Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
| | - Yuan Tao
- The State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
- Sauvage Laboratory for Smart Materials, Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
| | - Yan Huang
- The State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
- Sauvage Laboratory for Smart Materials, Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
| | - Mingyu Li
- The State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
- Sauvage Laboratory for Smart Materials, Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
| | - Hongjun Ji
- The State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
- Sauvage Laboratory for Smart Materials, Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, People's Republic of China
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29
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Hu J, Nie Z, Wang M, Liu Z, Huang S, Yang H. Springtail-inspired Light-driven Soft Jumping Robots Based on Liquid Crystal Elastomers with Monolithic Three-leaf Panel Fold Structure. Angew Chem Int Ed Engl 2023; 62:e202218227. [PMID: 36624053 DOI: 10.1002/anie.202218227] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/05/2023] [Accepted: 01/09/2023] [Indexed: 01/11/2023]
Abstract
Jump is an important form of motion that enables animals to escape from predators, increase their range of activities, and better adapt to the environment. Inspired by springtails, we describe a light-driven soft jumping robot based on a double-folded liquid crystal elastomer (LCE) ribbon actuator with a monolithic three-leaf panel fold structure. This robot can achieve remarkable jumping height, jumping distance, and maximum take-off velocity, of up to 87 body length (BL), 65 BL, and 930 BL s-1 , respectively, under near-infrared light irradiation. Further, it is possible to control the height, distance, and direction of jump by changing the size and crease angle of the double-folded LCE ribbon actuators. These robots can efficiently jump over obstacles and can jump continuously, even in complex environments. Our simple design strategy improves the performance of jumping actuators and we expect it to have a wide-ranging impact on the strength, continuity, and adaptability of future soft robots.
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Affiliation(s)
- Jun Hu
- Institute of Advanced Materials, School of Chemistry and Chemical Engineering, State Key Laboratory of Bioelectronics, and Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Southeast University, Nanjing, Jiangsu Province, 211189 (P. R. of, China
| | - Zhenzhou Nie
- Institute of Advanced Materials, School of Chemistry and Chemical Engineering, State Key Laboratory of Bioelectronics, and Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Southeast University, Nanjing, Jiangsu Province, 211189 (P. R. of, China
| | - Meng Wang
- Institute of Advanced Materials, School of Chemistry and Chemical Engineering, State Key Laboratory of Bioelectronics, and Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Southeast University, Nanjing, Jiangsu Province, 211189 (P. R. of, China
| | - Zhiyang Liu
- Institute of Advanced Materials, School of Chemistry and Chemical Engineering, State Key Laboratory of Bioelectronics, and Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Southeast University, Nanjing, Jiangsu Province, 211189 (P. R. of, China
| | - Shuai Huang
- Institute of Advanced Materials, School of Chemistry and Chemical Engineering, State Key Laboratory of Bioelectronics, and Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Southeast University, Nanjing, Jiangsu Province, 211189 (P. R. of, China
| | - Hong Yang
- Institute of Advanced Materials, School of Chemistry and Chemical Engineering, State Key Laboratory of Bioelectronics, and Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Southeast University, Nanjing, Jiangsu Province, 211189 (P. R. of, China
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30
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Upadhyay C, Ojha U. Stress-Induced Shape-Shifting Materials Possessing Autonomous Self-Healing and Scratch-Resistant Ability. Chem Asian J 2023; 18:e202201082. [PMID: 36637865 DOI: 10.1002/asia.202201082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/28/2022] [Accepted: 01/11/2023] [Indexed: 01/14/2023]
Abstract
Covalent adaptable networks (CANs) capable of both shape-shifting and self-healing ability offer a viable alternative to 4D printing technology to gain access to various complex shapes in a simplified manner. However, most of the reported CANs exhibit shape-shifting ability in the presence of temperature, light or chemical stimuli, which restricts their further utilization as realization of such a controlled environment is not feasible under complex scenarios. Herewith, we report a set of CANs based on a room-temperature exchangeable thia-Michael adduct, which undergoes rearrangement in network topology on application of external stress. These CANs with tensile strength (≤6 MPa) and modulus (≤71.4 MPa) adopt to any programmed shape under application of nominal stress. The CANs also exhibit stress-induced recyclability, self-welding and self-healing ability under ambient conditions. The transparency and ambient condition self-healing ability render these CANs to be utilized as scratch-resistant coatings on display items.
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Affiliation(s)
- Chandan Upadhyay
- Department of Chemistry, Rajiv Gandhi Institute of Petroleum Technology, Jais, Bahadurpur, UP, 229304, India
| | - Umaprasana Ojha
- Department of Chemistry, Rajiv Gandhi Institute of Petroleum Technology, Jais, Bahadurpur, UP, 229304, India
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31
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Lei Y, Yuan Y, Zhao S, Yuan A, Zhou S, Xiao Y, lei J, Jiang L. Catalyst-free, highly sensitive and adjustable photo-responsive azobenzene liquid crystal elastomers based on dynamic multiple hydrogen bond. POLYMER 2023. [DOI: 10.1016/j.polymer.2023.125737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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32
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Cao S, Bo R, Zhang Y. Polymeric Scaffolds for Regeneration of Central/Peripheral Nerves and Soft Connective Tissues. ADVANCED NANOBIOMED RESEARCH 2023. [DOI: 10.1002/anbr.202200147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- Shunze Cao
- Applied Mechanics Laboratory Department of Engineering Mechanics Laboratory for Flexible Electronics Technology Tsinghua University Beijing 100084 China
| | - Renheng Bo
- Applied Mechanics Laboratory Department of Engineering Mechanics Laboratory for Flexible Electronics Technology Tsinghua University Beijing 100084 China
| | - Yihui Zhang
- Applied Mechanics Laboratory Department of Engineering Mechanics Laboratory for Flexible Electronics Technology Tsinghua University Beijing 100084 China
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33
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Lewis KL, Herbert KM, Matavulj VM, Hoang JD, Ellison ET, Bauman GE, Herman JA, White TJ. Programming Orientation in Liquid Crystalline Elastomers Prepared with Intra-Mesogenic Supramolecular Bonds. ACS APPLIED MATERIALS & INTERFACES 2023; 15:3467-3475. [PMID: 36598490 DOI: 10.1021/acsami.2c18993] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The large, directional stimuli-response of aligned liquid crystalline elastomers (LCEs) could enable functional utility in robotics, medicine, consumer goods, and photonics. The alignment of LCEs has historically been realized via mechanical alignment of a two-stage reaction. Recent reports widely utilize chain extension reactions of liquid crystal monomers (LCM) to form LCEs that are subject to either surface-enforced or mechanical alignment. Here, we prepare LCEs that contain intra-mesogenic supramolecular bonds synthesized via direct free-radical chain transfer photopolymerization processible by a distinctive mechanical alignment mechanism. The LCEs were prepared by the polymerization of a benzoic acid monomer (11OBA), which dimerized to form a liquid crystal monomer, with a diacrylate LCM (C6M). The incorporation of the intra-mesogenic hydrogen bonds increases the achievable nematic order from mechanical programming. Accordingly, LCEs prepared with larger 11OBA concentration exhibit higher magnitude thermomechanical strain values when compared to a LCE containing only covalent bonds. These LCEs can be reprogrammed with heat to return the aligned film to the polydomain state. The LCE can then be subsequently programmed to orient in a different direction. The facile preparation of (re)programmable LCEs with supramolecular bonds opens new avenues for the implementation of these materials as shape deployable elements.
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Affiliation(s)
- Kristin L Lewis
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Katie M Herbert
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Valentina M Matavulj
- Material Science and Engineering Program, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Jonathan D Hoang
- Material Science and Engineering Program, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Eric T Ellison
- Department of Geological Sciences, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Grant E Bauman
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Jeremy A Herman
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado80309, United States
| | - Timothy J White
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado80309, United States
- Material Science and Engineering Program, University of Colorado Boulder, Boulder, Colorado80309, United States
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34
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Park M, Stricker F, Campos JG, Clark KD, Lee J, Kwon Y, Valentine MT, Read de Alaniz J. Design of Surface-Aligned Main-Chain Liquid-Crystal Networks Prepared under Ambient, Light-Free Conditions Using the Diels-Alder Cycloaddition. ACS Macro Lett 2023; 12:33-39. [PMID: 36541858 DOI: 10.1021/acsmacrolett.2c00616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Surface-aligned liquid-crystal networks (LCNs) offer a solution for developing functional materials capable of performing a range of tasks, including actuation, shape memory, and surfaces patterning. Here we show that Diels-Alder cycloaddition can be used to prepare the backbone of planar aligned LCNs under mild ambient conditions without the addition of additives or UV irradiation. The mechanical properties of the networks have robust viscoelastic modulus and stiffness with a reversible local free volume change upon physical aging. This study shows new opportunities to design surface-aligned LCNs based on additive free step-growth Diels-Alder polymerization and enables the potential to incorporate a wider range of photochromic materials into LCNs.
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Affiliation(s)
- Minwook Park
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara 93106, California, United States
| | - Friedrich Stricker
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara 93106, California, United States
| | - Jesus Guillen Campos
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara 93106, California, United States
| | - Kyle D Clark
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara 93106, California, United States
| | - Jaejun Lee
- Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Younghoon Kwon
- Department of Mechanical Engineering, University of California-Santa Barbara, Santa Barbara 93106, California, United States
| | - Megan T Valentine
- Department of Mechanical Engineering, University of California-Santa Barbara, Santa Barbara 93106, California, United States
| | - Javier Read de Alaniz
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara 93106, California, United States
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35
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Liang H, Zhang S, Liu Y, Yang Y, Zhang Y, Wu Y, Xu H, Wei Y, Ji Y. Merging the Interfaces of Different Shape-Shifting Polymers Using Hybrid Exchange Reactions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2202462. [PMID: 36325655 DOI: 10.1002/adma.202202462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Sophisticated shape-shifting structures and integration of advanced functions often call for different-chemistry-based polymers (such as epoxy and polyurethane) in a unified system. However, permanent cross-links pose crucial obstacles to be seamless. Here, merging interfaces via hybrid exchange reactions among different dynamic covalent bonds (including ester, urethane, thiourethane, boronic-ester, and oxime-ester linkages) is proposed, breaking the long-lasting restriction that these widely used bonds only undergo self-exchange reactions. Model compound studies are conducted to verify that hybrid exchange reactions occur. As demonstrations, different liquid crystal elastomers are tenaciously joined into coherent assemblies, with the desired biomimetic structures (e.g., flying fish containing stiff and flexible parts) and rare deformation modes (e.g., flower blooming upon both heating and cooling). Besides connecting polymers, hybrid exchange reactions also facilitate the creation of new materials through cross-fusion of different polymers. In addition to the polymers used in this work, hybrid exchange reactions can be adapted to other polymers based on similar mechanisms and beyond. Besides shape-shifting-related areas (e.g., soft robots, flexible electronics, and biomedical devices), it may also foster innovation in other fields involving general polymers, as well as promote deeper understanding of dynamic covalent chemistry.
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Affiliation(s)
- Huan Liang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Shuai Zhang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yawen Liu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yang Yang
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, China
| | - Yubai Zhang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yahe Wu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hongtu Xu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yen Wei
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
- Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung-Yuan Christian University, Chung-Li, Taiwan, 32023, China
| | - Yan Ji
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
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36
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Ahmadpour-Samani P, Zahedi P. An investigation on nematic-isotropic phase transition, viscosity and diffusion coefficient of liquid crystalline elastomers at different temperatures using molecular dynamics simulation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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37
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Gao J, He Y, Cong X, Yi H, Guo J. Reconfigurable Fluorescent Liquid Crystal Elastomers for Integrated Visual and Haptic Information Storage. ACS APPLIED MATERIALS & INTERFACES 2022; 14:53348-53358. [PMID: 36395006 DOI: 10.1021/acsami.2c17494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The rapid advancements in information technology require new information storage and display materials. However, the development of on-demand information storage systems with multiple modes remains a significant challenge. As a pioneering approach, this study designed an integrated visual and haptic information storage and display using a reconfigurable fluorescent liquid crystal elastomer (FLCE) with dynamic covalent bonds. The FLCEs were fabricated in two steps of amine-acrylate aza-Michael addition and photopolymerization, and they simultaneously exhibited phototunable fluorescence caused by the reversible Z/E photoisomerization of the chromophores and a reprogrammable shape owing to the catalyst-free transesterification. In addition, we established various information storage and display modes featuring the characteristics of reversibly photoswitchable fluorescence, shape memory, and thermally reconfigurable shape with a reconfigurable FLCE system. Moreover, a strategy to display the information by incorporating both visual and haptic feedback is implemented for fulfilling the needs of the visually impaired and related users. Such reconfigurable FLCE systems will aid in the development of on-demand information storage, display, and protection devices.
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Affiliation(s)
- Jingjing Gao
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing100029, China
| | - Yanrong He
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing100029, China
| | - Xiaoyang Cong
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing100029, China
| | - Huijie Yi
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing100029, China
| | - Jinbao Guo
- Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education, and College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing100029, China
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38
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Wang J, Zhang H, Lei J, Wu M, Liu W, Qu JP. Stress-Free Two-Way Shape-Memory Mechanism of a Semicrystalline Network with a Broad Melting Transition. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Jin Wang
- National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou510641, China
- Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou510641, China
- Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou510641, China
| | - He Zhang
- National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou510641, China
- Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou510641, China
- Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou510641, China
| | - Junjie Lei
- School of Chemistry and Chemical Engineering, Guangdong Provincial Key Lab of Green Chemical Product Technology, South China University of Technology, Guangzhou510640, China
| | - Mengxuan Wu
- National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou510641, China
- Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou510641, China
- Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou510641, China
| | - Weifeng Liu
- School of Chemistry and Chemical Engineering, Guangdong Provincial Key Lab of Green Chemical Product Technology, South China University of Technology, Guangzhou510640, China
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou510640, China
| | - Jin-Ping Qu
- National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou510641, China
- Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou510641, China
- Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou510641, China
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39
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Hebner TS, Kirkpatrick BE, Anseth KS, Bowman CN, White TJ. Surface-Enforced Alignment of Reprogrammable Liquid Crystalline Elastomers. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2204003. [PMID: 35988144 PMCID: PMC9561760 DOI: 10.1002/advs.202204003] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/04/2022] [Indexed: 05/31/2023]
Abstract
Liquid crystalline elastomers (LCEs) are stimuli-responsive materials capable of undergoing large deformations. The thermomechanical response of LCEs is attributable to the coupling of polymer network properties and disruption of order between liquid crystalline mesogens. Complex deformations have been realized in LCEs by either programming the nematic director via surface-enforced alignment or localized mechanical deformation in materials incorporating dynamic covalent chemistries. Here, the preparation of LCEs via thiol-Michael addition reaction is reported that are amenable to surface-enforced alignment. Afforded by the thiol-Michael addition reaction, dynamic covalent bonds are uniquely incorporated in chemistries subject to surface-enforce alignment. Accordingly, LCEs prepared with complex director profiles are able to be programmed and reprogrammed by (re)activating the dynamic covalent chemistry to realize distinctive shape transformations.
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Affiliation(s)
- Tayler S. Hebner
- Department of Chemical and Biological EngineeringUniversity of ColoradoBoulderCO80303USA
| | - Bruce E. Kirkpatrick
- Department of Chemical and Biological EngineeringUniversity of ColoradoBoulderCO80303USA
- Medical Scientist Training ProgramUniversity of Colorado Anschutz Medical CampusAuroraCO80045USA
| | - Kristi S. Anseth
- Department of Chemical and Biological EngineeringUniversity of ColoradoBoulderCO80303USA
- Materials Science and Engineering ProgramUniversity of ColoradoBoulderCO80303USA
| | - Christopher N. Bowman
- Department of Chemical and Biological EngineeringUniversity of ColoradoBoulderCO80303USA
- Materials Science and Engineering ProgramUniversity of ColoradoBoulderCO80303USA
| | - Timothy J. White
- Department of Chemical and Biological EngineeringUniversity of ColoradoBoulderCO80303USA
- Materials Science and Engineering ProgramUniversity of ColoradoBoulderCO80303USA
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40
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Choi S, Kim B, Park S, Seo JH, Ahn SK. Slidable Cross-Linking Effect on Liquid Crystal Elastomers: Enhancement of Toughness, Shape-Memory, and Self-Healing Properties. ACS APPLIED MATERIALS & INTERFACES 2022; 14:32486-32496. [PMID: 35792581 DOI: 10.1021/acsami.2c06462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The network structures of liquid crystal elastomers (LCEs) are crucial to impart rubbery behavior to LCEs and enable reversible actuation. Most LCEs developed to date are covalently linked, implying that the cross-links are fixed at a particular position. Herein, we report a new class of LCEs integrating polyrotaxanes (PRs) as slidable cross-links (PR-LCEs). Interestingly, the incorporation of a low loading (0.3-2.0 wt %) of the PR cross-linkers to the LCE causes a significant impact on various properties of the resulting PR-LCEs due to the pulley effect. The optimum PR loading is determined to be 0.5 wt %, at which point the toughness and damping behavior are maximized. The robust mechanical properties of the PR-LCE offers a superior actuation performance to that of the pristine LCE along with an excellent quadruple shape-memory effect. Furthermore, the incorporation of PR is useful to enhance the efficiency of shape-memory-assisted self-healing when heating above the nematic-isotropic transition.
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Affiliation(s)
- Subi Choi
- Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Bitgaram Kim
- Department of Materials Science and Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Sungmin Park
- Advanced Materials Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Ji-Hun Seo
- Department of Materials Science and Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Suk-Kyun Ahn
- Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Republic of Korea
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41
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Guan Z, Wang L, Bae J. Advances in 4D printing of liquid crystalline elastomers: materials, techniques, and applications. MATERIALS HORIZONS 2022; 9:1825-1849. [PMID: 35504034 DOI: 10.1039/d2mh00232a] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Liquid crystalline elastomers (LCEs) are polymer networks exhibiting anisotropic liquid crystallinity while maintaining elastomeric properties. Owing to diverse polymeric forms and self-alignment molecular behaviors, LCEs have fascinated state-of-the-art efforts in various disciplines other than the traditional low-molar-mass display market. By patterning order to structures, LCEs demonstrate reversible high-speed and large-scale actuations in response to external stimuli, allowing for close integration with 4D printing and architectures of digital devices, which is scarcely observed in homogeneous soft polymer networks. In this review, we collect recent advances in 4D printing of LCEs, with emphases on synthesis and processing methods that enable microscopic changes in the molecular orientation and hence macroscopic changes in the properties of end-use objects. Promising potentials of printed complexes include fields of soft robotics, optics, and biomedical devices. Within this scope, we elucidate the relationships among external stimuli, tailorable morphologies in mesophases of liquid crystals, and programmable topological configurations of printed parts. Lastly, perspectives and potential challenges facing 4D printing of LCEs are discussed.
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Affiliation(s)
- Zhecun Guan
- Department of Nanoengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Ling Wang
- School of Materials Science and Engineering, Tianjin University, Tianjin 300350, P. R. China.
| | - Jinhye Bae
- Department of Nanoengineering, University of California San Diego, La Jolla, CA 92093, USA.
- Chemical Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
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42
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Li T, Liu F, Yang X, Hao S, Cheng Y, Li S, Zhu H, Song H. Muscle-Mimetic Highly Tough, Conductive, and Stretchable Poly(ionic liquid) Liquid Crystalline Ionogels with Ultrafast Self-Healing, Super Adhesive, and Remarkable Shape Memory Properties. ACS APPLIED MATERIALS & INTERFACES 2022; 14:29261-29272. [PMID: 35699738 DOI: 10.1021/acsami.2c06662] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Here, we report a simple method for preparing muscle-mimetic highly tough, conductive, and stretchable liquid crystalline ionogels which contains only one poly(ionic liquid) (PIL) in an ionic liquid via in situ free radical photohomopolymerization by using nitrogen gas instead of air atmosphere. Due to eliminating the inhibition caused by dissolved oxygen, the polymerization under nitrogen gas has much higher molecular weight, lower critical sol-gel concentration, and stronger mechanical properties. More importantly, benefiting from the unique loofah-like microstructures along with the strong internal ionic interactions, entanglements of long PIL chains and liquid crystalline domains, the ionogels show special optical anisotropic, superstretchability (>8000%), high fracture strength (up to 16.52 MPa), high toughness (up to 39.22 MJ/m3), and have ultrafast self-healing, ultrastrong adhesive, and excellent shape memory properties. Due to its excellent stretchability and good conductive-strain responsiveness, the as-prepared ionogel can be easily applied for high-performance flexible and wearable sensors for motion detecting. Therefore, this paper provides an effective route and developed method to generate highly stretchable conductive liquid crystalline ionogels/elastomers that can be used in widespread flexible and wearable electronics.
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Affiliation(s)
- Tianci Li
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
| | - Fang Liu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
| | - Xuemeng Yang
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
| | - Shuai Hao
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
| | - Yan Cheng
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
| | - Shuaijie Li
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
| | - Hongnan Zhu
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
| | - Hongzan Song
- College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei Province 071002, P. R. China
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43
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Guo H, Saed MO, Terentjev EM. Thiol-acrylate side-chain liquid crystal elastomers. SOFT MATTER 2022; 18:4803-4809. [PMID: 35713099 PMCID: PMC9241586 DOI: 10.1039/d2sm00547f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
The Michael addition 'click' chemistry was used to graft acrylate-terminated mesogenic groups onto the polysiloxane backbone polymer chain with thiol functional groups, with a constant 15% fraction of diacrylate reacting monomers as crosslinkers. Three different types of mesogens were used, and also their 50 : 50 mixtures, and in all cases we have obtained the smectic-A phase of the resulting liquid crystalline elastomer. Using X-ray diffraction, calorimetry and dynamic mechanical analysis, we investigated the relationship between the molecular structure of mesogenic side groups and the structure and properties of the elastomers. The shape-memory of smectic elastomers was verified. The unusual features were the semi-crystalline nature of elastomers with non-polar mesogens and the clear role of side-by-side rod dimerization of polar mesogens leading to a higher smectic layer spacing. We investigated the evolution of the smectic alignment on uniaxial stretching along the layer normal and identified two distinct ways in which the elastomer responds: the coarsened Helfrich-Hurault zig-zag layer texture and the large-scale stripe domains of uniform layer rotation in the systems with lower order parameter and the associated layer constraints.
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Affiliation(s)
- Hongye Guo
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge, CB3 0HE, UK.
| | - Mohand O Saed
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge, CB3 0HE, UK.
| | - Eugene M Terentjev
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge, CB3 0HE, UK.
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44
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Wu Y, Zhang S, Yang Y, Li Z, Wei Y, Ji Y. Locally controllable magnetic soft actuators with reprogrammable contraction-derived motions. SCIENCE ADVANCES 2022; 8:eabo6021. [PMID: 35749490 PMCID: PMC9232107 DOI: 10.1126/sciadv.abo6021] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/10/2022] [Indexed: 06/01/2023]
Abstract
Reprogrammable magneto-responsive soft actuators capable of working in enclosed and confined spaces and adapting functions under changing situations are highly demanded for new-generation smart devices. Despite the promising prospect, the realization of versatile morphing modes (more than bending) and local magnetic control remains challenging but is crucial for further on-demand applications. Here, we address the challenges by maximizing the unexplored potential of magnetothermal responsiveness and covalent adaptable networks (CANs) in liquid crystalline elastomers (LCEs). Various magneto-actuated contraction-derived motions that were hard to achieve previously (e.g., bidirectional shrinkage and dynamic 3D patterns) can be attained, reprogrammed, and assembled seamlessly to endow functional diversity and complexity. By integration of LCEs with different magneto-responsive threshold values, local and sequential magnetic control is readily realized. Many magnetic actuation portfolios are performed by rationally imputing "logic switch" sequences. Meanwhile, our systems exhibit additional favorable performances including stepwise magnetic controllability, multiresponsiveness, self-healing, and remolding ability.
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Affiliation(s)
- Yahe Wu
- The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Shuai Zhang
- The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Yang Yang
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Zhen Li
- Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094, China
| | - Yen Wei
- The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Yan Ji
- The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 100084, China
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45
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Blanke M, Postulka L, Ciara I, D'Acierno F, Hildebrandt M, Gutmann JS, Dong RY, Michal CA, Giese M. Manipulation of Liquid Crystalline Properties by Dynamic Covalent Chemistry─En Route to Adaptive Materials. ACS APPLIED MATERIALS & INTERFACES 2022; 14:16755-16763. [PMID: 35377595 DOI: 10.1021/acsami.2c03241] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Dynamic covalent bonds bear great potential for the development of adaptive and self-healing materials. Herein, we introduce a versatile concept not only for the design of low-molecular-weight liquid crystals but also for their in situ postsynthetic modification by using the dynamic covalent nature of imine bonds. The methodology allows systematic investigations of structure-property relationships as well as the manipulation of the materials' behavior (liquid crystallinity) and the introduction of additional properties (here, fluorescence) by a solvent-free method. For the first time, the transamination reaction is followed by variable-temperature 19F solid-state NMR in the mesophase, providing insights into the reaction dynamics in a liquid crystalline material. Finally, the application potential for the design of liquid crystalline materials with adaptive properties is demonstrated by a sequential combination of these reactions.
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Affiliation(s)
- Meik Blanke
- Organic Chemistry, University of Duisburg-Essen, Universitätsstraße 7, 45117 Essen, Germany
| | - Leona Postulka
- Organic Chemistry, University of Duisburg-Essen, Universitätsstraße 7, 45117 Essen, Germany
| | - Isabelle Ciara
- Organic Chemistry, University of Duisburg-Essen, Universitätsstraße 7, 45117 Essen, Germany
| | - Francesco D'Acierno
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver BC V6T 1Z1, Canada
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver BC V6T 1Z1, Canada
| | - Marcus Hildebrandt
- Physical Chemistry, University of Duisburg-Essen, Universitätsstraße 2, 45117 Essen, Germany
| | - Jochen S Gutmann
- Physical Chemistry, University of Duisburg-Essen, Universitätsstraße 2, 45117 Essen, Germany
| | - Ronald Y Dong
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver BC V6T 1Z1, Canada
| | - Carl A Michal
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver BC V6T 1Z1, Canada
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver BC V6T 1Z1, Canada
| | - Michael Giese
- Organic Chemistry, University of Duisburg-Essen, Universitätsstraße 7, 45117 Essen, Germany
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46
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Li Y, Liu T, Ambrogi V, Rios O, Xia M, He W, Yang Z. Liquid Crystalline Elastomers Based on Click Chemistry. ACS APPLIED MATERIALS & INTERFACES 2022; 14:14842-14858. [PMID: 35319184 DOI: 10.1021/acsami.1c21096] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Liquid crystalline elastomers (LCEs) have emerged as an important class of functional materials that are suitable for a wide range of applications, such as sensors, actuators, and soft robotics. The unique properties of LCEs originate from the combination between liquid crystal and elastomeric network. The control of macroscopic liquid crystalline orientation and network structure is crucial to realizing the useful functionalities of LCEs. A variety of chemistries have been developed to fabricate LCEs, including hydrosilylation, free radical polymerization of acrylate, and polyaddition of epoxy and carboxylic acid. Over the past few years, the use of click chemistry has become a more robust and energy-efficient way to construct LCEs with desired structures. This article provides an overview of emerging LCEs based on click chemistries, including aza-Michael addition between amine and acrylate, radical-mediated thiol-ene and thiol-yne reactions, base-catalyzed thiol-acrylate and thiol-epoxy reactions, copper-catalyzed azide-alkyne cycloaddition, and Diels-Alder cycloaddition. The similarities and differences of these reactions are discussed, with particular attention focused on the strengths and limitations of each reaction for the preparation of LCEs with controlled structures and orientations. The compatibility of these reactions with the traditional and emerging processing techniques, such as surface alignment and additive manufacturing, are surveyed. Finally, the challenges and opportunities of using click chemistry for the design of LCEs with advanced functionalities and applications are discussed.
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Affiliation(s)
- Yuzhan Li
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Tuan Liu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Veronica Ambrogi
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Napoli 80125, Italy
| | - Orlando Rios
- Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Min Xia
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Wanli He
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhou Yang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
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47
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Lin X, Gablier A, Terentjev EM. Imine-Based Reactive Mesogen and Its Corresponding Exchangeable Liquid Crystal Elastomer. Macromolecules 2022; 55:821-830. [PMID: 35572090 PMCID: PMC9098173 DOI: 10.1021/acs.macromol.1c02432] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/26/2021] [Indexed: 11/28/2022]
Abstract
![]()
To date, exchangeable liquid crystalline
elastomers (xLCEs) have
been mainly fabricated by combining conventional LCEs with additional
exchangeable functional groups in their networks. While conventional
LCEs are frequently made from commercially available aromatic–ester
reacting mesogens or from mesogens based on a biphenyl core, such
reacting monomers are not optimized to fabricating xLCEs whose bond-exchange
reaction is fast and clean cut. Here, we develop a fast synthesis
route to produce a new type of reactive mesogen based on an aromatic–imine
structure that intrinsically enables a fast and stable bond-exchange
reaction in the resulting imine-based xLCE. This new xLCE displays
vitrimer plastic-flow behavior, and its bond-exchange activation energy
is calculated to be 54 kJ/mol. We also demonstrate that this xLCE
is thermally stable to withstand many recycling cycles without visible
decay, and its liquid crystallinity is preserved. Finally, we demonstrate
the reprogramming and realignment of the mesogen orientation in this
xLCE with the realigned xLCE capable of reversible thermal actuation.
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Affiliation(s)
- Xueyan Lin
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Alexandra Gablier
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Eugene M. Terentjev
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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Zhou Y, Wang L, Ma S, Zhang H. Fully Room-Temperature Reprogrammable, Reprocessable, and Photomobile Soft Actuators from a High-Molecular-Weight Main-Chain Azobenzene Crystalline Poly(ester-amide). ACS APPLIED MATERIALS & INTERFACES 2022; 14:3264-3273. [PMID: 34991314 DOI: 10.1021/acsami.1c18647] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Azobenzene (azo) polymer photoactuators with full room-temperature reprogrammability, reprocessability, and photomobility are highly desirable for large-scale applications, but their development remains a daunting challenge. Herein, a strategy is first presented for fabricating such advanced photoactuators from a high-molecular-weight main-chain azo crystalline poly(ester-amide) (PEA) prepared via Michael addition polymerization. This azo PEA can be readily processed into both physically cross-linked, uniaxially oriented fibers and films with high mechanical robustness and reversible photoinduced bending/unbending at room temperature. Importantly, the presence of both amide unit-induced hydrogen bonding and crystalline domains in such films and fibers endows them with dynamic, yet stable cross-linking points, which enable their easy reprogrammability under strain at room temperature into various three-dimensional (3D) shapes (e.g., film helicoid and spiral ribbon, fiber spring) capable of showing completely different shape-dependent photomobile modes. In particular, these reshaped photoactuators can maintain their accurate 3D shapes and highly reversible photoinduced motions even after being kept at 80 °C for 20 days or at 100 °C for 2 days. They can also be reprocessed and recycled from solution at room temperature. Such a multifunctional main-chain azo crystalline PEA can serve as a versatile platform for fabricating various photoactuators with desired 3D shapes and motion modes under mild ambient conditions.
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Affiliation(s)
- Yan Zhou
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
| | - Lei Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shengkui Ma
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
| | - Huiqi Zhang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), and College of Chemistry, Nankai University, Tianjin 300071, China
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Ma J, Yang Y, Valenzuela C, Zhang X, Wang L, Feng W. Mechanochromic, Shape‐Programmable and Self‐Healable Cholesteric Liquid Crystal Elastomers Enabled by Dynamic Covalent Boronic Ester Bonds. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jiazhe Ma
- School of Materials Science and Engineering Tianjin University Tianjin 300350
| | - Yanzhao Yang
- School of Materials Science and Engineering Tianjin University Tianjin 300350
| | - Cristian Valenzuela
- School of Materials Science and Engineering Tianjin University Tianjin 300350
| | - Xuan Zhang
- School of Materials Science and Engineering Tianjin University Tianjin 300350
| | - Ling Wang
- School of Materials Science and Engineering Tianjin University Tianjin 300350
| | - Wei Feng
- School of Materials Science and Engineering Tianjin University Tianjin 300350
- Tianjin Key Laboratory of Composite and Functional Materials Tianjin 300350 P. R. China
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50
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Ohzono T, Koyama E. Effects of photo-isomerizable side groups on the phase and mechanical properties of main-chain nematic elastomers. Polym Chem 2022. [DOI: 10.1039/d2py00256f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of main-chain nematic liquid crystal elastomers containing various photo-isomerizable side groups branching from the main chain were synthesized. The effects of the side groups on the thermal phase and mechanical properties were explored.
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Affiliation(s)
- Takuya Ohzono
- Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | - Emiko Koyama
- Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8565, Japan
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