1
|
Wang S, Li S, Zhao W, Zhou Y, Wang L, Aizenberg J, Zhu P. Programming hierarchical anisotropy in microactuators for multimodal actuation. LAB ON A CHIP 2024; 24:4073-4084. [PMID: 39115160 DOI: 10.1039/d4lc00369a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/21/2024]
Abstract
Microactuators, capable of executing tasks typically repetitive, hazardous, or impossible for humans, hold great promise across fields such as precision medicine, environmental remediation, and swarm intelligence. However, intricate motions of microactuators normally require high complexity in design, making it increasingly challenging to realize at small scales using existing fabrication techniques. Taking inspiration from the hierarchical-anisotropy principle found in nature, we program liquid crystalline elastomer (LCE) microactuators with multimodal actuation tailored to their molecular, shape, and architectural anisotropies at (sub)nanometer, micrometer, and (sub)millimeter scales, respectively. Our strategy enables diverse deformations with individual LCE microstructures, including expanding, contracting, twisting, bending, and unwinding, as well as re-programmable shape transformations of assembled LCE architectures with negative Poisson's ratios, locally adjustable actuation, and changing from two-dimensional (2D) to three-dimensional (3D) structures. Furthermore, we design tetrahedral microactuators with well-controlled mobility and precise manipulation of both solids and liquids in various environments. This study provides a paradigm shift in the development of microactuators, unlocking a vast array of complexities achievable through manipulation at each hierarchical level of anisotropy.
Collapse
Affiliation(s)
- Shiyu Wang
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Shucong Li
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Wenchang Zhao
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Ying Zhou
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Liqiu Wang
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
| | - Joanna Aizenberg
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Pingan Zhu
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China.
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
| |
Collapse
|
2
|
Zhang X, Wei J, Qin L, Yu Y. Liquid crystal polymer actuators with complex and multiple actuations. J Mater Chem B 2024; 12:6757-6773. [PMID: 38916076 DOI: 10.1039/d4tb01055h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Deformable liquid crystal polymers (LCPs), which exhibit both entropic elasticity of polymer networks and anisotropic properties originating from ordered mesogens, have gained more and more interest for use as biomedical soft actuators. Especially, LCP actuators with controllable mesogen alignment, sophisticated geometry and reprogrammability are a rising star on the horizon of soft actuators, since they enable complex and multiple actuations. This review focuses on two topics: (1) the regulation of mesogen alignment and geometry of LCP actuators for complex actuations; (2) newly designed reprogrammable LCP materials for multiple actuations. First, basic actuation mechanisms are briefly introduced. Then, LCP actuators with complex actuations are demonstrated. Special attention is devoted to the improvement of fabrication methods, which profoundly influence the available complexity of the mesogen alignment and geometry. Subsequently, reprogrammable LCP actuators featuring dynamic networks or shape memory effects are discussed, with an emphasis on their multiple actuations. Finally, perspectives on the current challenges and potential development trends toward more intelligent LCP actuators are discussed, which may shed light on future investigations in this field.
Collapse
Affiliation(s)
- Xiaoyu Zhang
- Department of Materials Science & State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, 200433, China.
| | - Jia Wei
- Department of Materials Science & State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, 200433, China.
| | - Lang Qin
- Department of Materials Science & State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, 200433, China.
| | - Yanlei Yu
- Department of Materials Science & State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, 200433, China.
| |
Collapse
|
3
|
Cheng M, Cai W, Wang Z, Chen L, Yuan D, Ma Z, Bai Z, Kong D, Cen M, Xu S, Srivastava AK, Liu YJ. Responsive Liquid Crystal Network Microstructures with Customized Shapes and Predetermined Morphing for Adaptive Soft Micro-Optics. ACS APPLIED MATERIALS & INTERFACES 2024; 16:31776-31787. [PMID: 38858834 DOI: 10.1021/acsami.4c04275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
Stimuli-responsive materials have garnered substantial interest in recent years, particularly liquid crystal networks (LCNs) with sophisticatedly designed structures and morphing capabilities. Extensive efforts have been devoted to LCN structural designs spanning from two-dimensional (2D) to three-dimensional (3D) configurations and their intricate morphing behaviors through designed alignment. However, achieving microscale structures and large-area preparation necessitates the development of novel techniques capable of facilely fabricating LCN microstructures with precise control over both overall shape and alignment, enabling a 3D-to-3D shape change. Herein, a simple and cost-effective in-cell soft lithography (ICSL) technique is proposed to create LCN microstructures with customized shapes and predesigned morphing. The ICSL technique involves two sequential steps: fabricating the desired microstructure as the template by using the photopolymerization-induced phase separation (PIPS) method and reproducing the LCN microstructures through templating. Meanwhile, surface anchoring is employed to design and achieve molecular alignment, accommodating different deformation modes. With the proposed ICSL technique, cylindrical and spherical microlens arrays (CMLAs and SMLAs) have been successfully fabricated with stimulus-driven polarization-dependent focusing effects. This technique offers distinct advantages including high customizability, large-area production, and cost-effectiveness, which pave a new avenue for extensive applications in different fields, exemplified by adaptive soft micro-optics and photonics.
Collapse
Affiliation(s)
- Ming Cheng
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Advanced Displays and Optoelectronics Technologies, and Centre for Display Research, Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Wenfeng Cai
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zhenming Wang
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Lei Chen
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Dandan Yuan
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zongjun Ma
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Ziyan Bai
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Delai Kong
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Mengjia Cen
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Shaolin Xu
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Abhishek Kumar Srivastava
- State Key Laboratory of Advanced Displays and Optoelectronics Technologies, and Centre for Display Research, Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Yan Jun Liu
- Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
- State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Southern University of Science and Technology, Shenzhen 518055, China
| |
Collapse
|
4
|
Lyu P, Broer DJ, Liu D. Advancing interactive systems with liquid crystal network-based adaptive electronics. Nat Commun 2024; 15:4191. [PMID: 38760356 PMCID: PMC11101476 DOI: 10.1038/s41467-024-48353-7] [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: 02/05/2024] [Accepted: 04/25/2024] [Indexed: 05/19/2024] Open
Abstract
Achieving adaptive behavior in artificial systems, analogous to living organisms, has been a long-standing goal in electronics and materials science. Efforts to integrate adaptive capabilities into synthetic electronics traditionally involved a typical architecture comprising of sensors, an external controller, and actuators constructed from multiple materials. However, challenges arise when attempting to unite these three components into a single entity capable of independently coping with dynamic environments. Here, we unveil an adaptive electronic unit based on a liquid crystal polymer that seamlessly incorporates sensing, signal processing, and actuating functionalities. The polymer forms a film that undergoes anisotropic deformations when exposed to a minor heat pulse generated by human touch. We integrate this property into an electric circuit to facilitate switching. We showcase the concept by creating an interactive system that features distributed information processing including feedback loops and enabling cascading signal transmission across multiple adaptive units. This system responds progressively, in a multi-layered cascade to a dynamic change in its environment. The incorporation of adaptive capabilities into a single piece of responsive material holds immense potential for expediting progress in next-generation flexible electronics, soft robotics, and swarm intelligence.
Collapse
Affiliation(s)
- Pengrong Lyu
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands
| | - Dirk J Broer
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands
| | - Danqing Liu
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands.
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands.
| |
Collapse
|
5
|
Waters JT, Balazs AC. Achieving controllable and reversible snap-through in pre-strained strips of liquid crystalline elastomers. SOFT MATTER 2024; 20:3256-3270. [PMID: 38512704 DOI: 10.1039/d4sm00037d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Deformable, elastic materials that buckle in response to external stimuli can display "snap-through", which involves a transition between different, stable buckled states. Snap-through produces a quick release of stored potential energy, and thus can provide fast actuation for soft robots and other flexible devices. Liquid crystalline elastomers (LCEs) exposed to light undergo a phase transition and a concomitant mechanical deformation, allowing control of snap-through for rapid, large amplitude actuation. Using both a semi-analytical model and finite element simulations, we focus on a thin LCE strip that is clamped at both ends and buckles due to an initially imposed strain. We show that when this clamped, strained sample is exposed to light, it produces controllable snap-through behavior, which can be regulated by varying the light intensity and the area of the sample targeted by light. In particular, this snap-through can be triggered in different directions, allowing the system to be reset and triggered multiple times. Removing the light source will cause the system to settle into one of two stable states, enabling the encoding and storage of information in the system. We also highlight a specific case where removing the light source removes the induced buckling and returns the material to an initially flat state. In this case, the system can be reset and form a new shape, allowing it to function as a rewriteable haptic interface.
Collapse
Affiliation(s)
- James T Waters
- University of Pittsburgh, Department of Chemical and Petroleum Engineering, USA.
| | - Anna C Balazs
- University of Pittsburgh, Department of Chemical and Petroleum Engineering, USA.
| |
Collapse
|
6
|
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.
Collapse
Affiliation(s)
- Andraž Rešetič
- Jožef Stefan Institute, Solid State Physics Department, Jamova cesta 39, 1000, Ljubljana, Slovenia.
| |
Collapse
|
7
|
Xu Y, Zhang X, Song Z, Chen X, Huang Y, Wang J, Li B, Huang S, Li Q. In situ Light-Writable Orientation Control in Liquid Crystal Elastomer Film Enabled by Chalcones. Angew Chem Int Ed Engl 2024; 63:e202319698. [PMID: 38190301 DOI: 10.1002/anie.202319698] [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: 12/19/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 01/10/2024]
Abstract
Liquid crystal elastomers (LCEs) are stimulus-responsive materials with intrinsic anisotropy. However, it is still challenging to in situ program the mesogen alignment to realize three-dimensional (3D) deformations with high-resolution patterned structures. This work presents a feasible strategy to program the anisotropy of LCEs by using chalcone mesogens that can undergo a photoinduced cycloaddition reaction under linear polarized light. It is shown that by controlling the polarization director and the irradiation region, patterned alignment distribution in a freestanding LCE film can be created, which leads to complex and reversible 3D shape-morphing behaviors. The work demonstrates an in situ light-writing method to achieve sophisticated topography changes in LCEs, which has potential applications in encryption, sensors, and beyond.
Collapse
Affiliation(s)
- Yiyi Xu
- Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China
| | - Xinfang Zhang
- Materials Science Graduate Program, Kent State University, Kent, OH-44242, USA
| | - Zhenpeng Song
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, 210023, China
| | - Xiao Chen
- Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China
| | - Yinliang Huang
- Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China
| | - Jinyu Wang
- Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China
| | - Bingxiang Li
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, 210023, China
| | - Shuai Huang
- Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China
| | - Quan Li
- Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China
- Materials Science Graduate Program, Kent State University, Kent, OH-44242, USA
| |
Collapse
|
8
|
Feng X, Wang L, Xue Z, Xie C, Han J, Pei Y, Zhang Z, Guo W, Lu B. Melt electrowriting enabled 3D liquid crystal elastomer structures for cross-scale actuators and temperature field sensors. SCIENCE ADVANCES 2024; 10:eadk3854. [PMID: 38446880 PMCID: PMC10917348 DOI: 10.1126/sciadv.adk3854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/30/2024] [Indexed: 03/08/2024]
Abstract
Liquid crystal elastomers (LCEs) have garnered attention for their remarkable reversible strains under various stimuli. Early studies on LCEs mainly focused on basic dimensional changes in macrostructures or quasi-three-dimensional (3D) microstructures. However, fabricating complex 3D microstructures and cross-scale LCE-based structures has remained challenging. In this study, we report a compatible method named melt electrowriting (MEW) to fabricate LCE-based microfiber actuators and various 3D actuators on the micrometer to centimeter scales. By controlling printing parameters, these actuators were fabricated with high resolutions (4.5 to 60 μm), actuation strains (10 to 55%), and a maximum work density of 160 J/kg. In addition, through the integration of a deep learning-based model, we demonstrated the application of LCE materials in temperature field sensing. Large-scale, real-time, LCE grid-based spatial temperature field sensors have been designed, exhibiting a low response time of less than 42 ms and a high precision of 94.79%.
Collapse
Affiliation(s)
- Xueming Feng
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
| | - Li Wang
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
- National Innovation Institute of Additive Manufacturing, No. 997, Shanglinyuan 8th Road, Gaoxin District, Xi’an 710300, China
| | - Zhengjie Xue
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
| | - Chao Xie
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
| | - Jie Han
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany
| | - Yuechen Pei
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
| | - Zhaofa Zhang
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
| | - Wenhua Guo
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
- National Innovation Institute of Additive Manufacturing, No. 997, Shanglinyuan 8th Road, Gaoxin District, Xi’an 710300, China
| | - Bingheng Lu
- The State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710054, China
- National Innovation Institute of Additive Manufacturing, No. 997, Shanglinyuan 8th Road, Gaoxin District, Xi’an 710300, China
| |
Collapse
|
9
|
Pinchin NP, Guo H, Meteling H, Deng Z, Priimagi A, Shahsavan H. Liquid Crystal Networks Meet Water: It's Complicated! ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2303740. [PMID: 37392137 DOI: 10.1002/adma.202303740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/21/2023] [Accepted: 06/29/2023] [Indexed: 07/03/2023]
Abstract
Soft robots are composed of compliant materials that facilitate high degrees of freedom, shape-change adaptability, and safer interaction with humans. An attractive choice of material for soft robotics is crosslinked networks of liquid crystal polymers (LCNs), as they are responsive to a wide variety of external stimuli and capable of undergoing fast, programmable, complex shape morphing, which allows for their use in a wide range of soft robotic applications. However, unlike hydrogels, another popular material in soft robotics, LCNs have limited applicability in flooded or aquatic environments. This can be attributed not only to the poor efficiency of common LCN actuation methods underwater but also to the complicated relationship between LCNs and water. In this review, the relationship between water and LCNs is elaborated and the existing body of literature is surveyed where LCNs, both hygroscopic and non-hygroscopic, are utilized in aquatic soft robotic applications. Then the challenges LCNs face in widespread adaptation to aquatic soft robotic applications are discussed and, finally, possible paths forward for their successful use in aquatic environments are envisaged.
Collapse
Affiliation(s)
- Natalie P Pinchin
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Hongshuang Guo
- Smart Photonic Materials, Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33101, Finland
| | - Henning Meteling
- Smart Photonic Materials, Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33101, Finland
| | - Zixuan Deng
- Smart Photonic Materials, Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33101, Finland
| | - Arri Priimagi
- Smart Photonic Materials, Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33101, Finland
| | - Hamed Shahsavan
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| |
Collapse
|
10
|
den Hoed FM, Carlotti M, Palagi S, Raffa P, Mattoli V. Evolution of the Microrobots: Stimuli-Responsive Materials and Additive Manufacturing Technologies Turn Small Structures into Microscale Robots. MICROMACHINES 2024; 15:275. [PMID: 38399003 PMCID: PMC10893381 DOI: 10.3390/mi15020275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/02/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024]
Abstract
The development of functional microsystems and microrobots that have characterized the last decade is the result of a synergistic and effective interaction between the progress of fabrication techniques and the increased availability of smart and responsive materials to be employed in the latter. Functional structures on the microscale have been relevant for a vast plethora of technologies that find application in different sectors including automotive, sensing devices, and consumer electronics, but are now also entering medical clinics. Working on or inside the human body requires increasing complexity and functionality on an ever-smaller scale, which is becoming possible as a result of emerging technology and smart materials over the past decades. In recent years, additive manufacturing has risen to the forefront of this evolution as the most prominent method to fabricate complex 3D structures. In this review, we discuss the rapid 3D manufacturing techniques that have emerged and how they have enabled a great leap in microrobotic applications. The arrival of smart materials with inherent functionalities has propelled microrobots to great complexity and complex applications. We focus on which materials are important for actuation and what the possibilities are for supplying the required energy. Furthermore, we provide an updated view of a new generation of microrobots in terms of both materials and fabrication technology. While two-photon lithography may be the state-of-the-art technology at the moment, in terms of resolution and design freedom, new methods such as two-step are on the horizon. In the more distant future, innovations like molecular motors could make microscale robots redundant and bring about nanofabrication.
Collapse
Affiliation(s)
- Frank Marco den Hoed
- Center for Materials Interfaces, Istituto Italiano di Tecnologia, Via R. Piaggio 34, 56025 Pontedera, Italy;
- Smart and Sustainable Polymeric Products, Engineering and Technology Institute Groningen (ENTEG), University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands;
| | - Marco Carlotti
- Center for Materials Interfaces, Istituto Italiano di Tecnologia, Via R. Piaggio 34, 56025 Pontedera, Italy;
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy
| | - Stefano Palagi
- BioRobotics Institute, Sant’Anna School of Advanced Studies, P.zza Martiri della Libertà 33, 56127 Pisa, Italy;
| | - Patrizio Raffa
- Smart and Sustainable Polymeric Products, Engineering and Technology Institute Groningen (ENTEG), University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands;
| | - Virgilio Mattoli
- Center for Materials Interfaces, Istituto Italiano di Tecnologia, Via R. Piaggio 34, 56025 Pontedera, Italy;
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
Ube T, Suka I, Ogikubo S, Hashimoto G, Suda M, Yamamoto HM, Ikeda T. Inducing Motions of Polymers in Liquid Nitrogen with Light. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2306402. [PMID: 37867200 DOI: 10.1002/adma.202306402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 09/02/2023] [Indexed: 10/24/2023]
Abstract
Polymer materials that show macroscopic deformation in response to external stimuli are feasible for novel soft actuators including microactuators. Incorporation of photochromic moieties, such as azobenzenes, into polymer networks enables macroscopic deformation under irradiation with light through photoisomerization. Under cryogenic conditions, however, it has been difficult to induce macroscopic deformation as polymers lose their soft nature due to the severe restrictions of molecular motions. Here, activation of molecular motions and macroscopic deformation in liquid nitrogen only with light for polymers containing photochromic moieties is reported. Photoinduced bending of polymer networks with normal azobenzenes in liquid nitrogen is enabled by preliminary UV irradiation at room temperature to produce cis-isomers. To realize photoinduced deformation directly in liquid nitrogen, polymer networks are functionalized with bridged azobenzenes, which exist as cis-isomers in thermodynamic equilibrium. The films with bridged azobenzenes exhibit reversible photoisomerization and bending upon irradiation with light in liquid nitrogen without the need of preliminary irradiation, implying that the change in conformation of polymer chains can be isothermally induced even under cryogenic conditions. Achievement of flexible motions under cryogenic conditions through isothermal processes will greatly expand the operating temperature range of soft actuators.
Collapse
Affiliation(s)
- Toru Ube
- Research & Development Initiative, Chuo University, Tokyo, 112-8551, Japan
| | - Ikumi Suka
- Graduate School of Science and Engineering, Chuo University, Tokyo, 112-8551, Japan
| | - Shunya Ogikubo
- Graduate School of Science and Engineering, Chuo University, Tokyo, 112-8551, Japan
| | - Gaku Hashimoto
- Graduate School of Science and Engineering, Chuo University, Tokyo, 112-8551, Japan
| | - Masayuki Suda
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan
| | | | - Tomiki Ikeda
- Research & Development Initiative, Chuo University, Tokyo, 112-8551, Japan
| |
Collapse
|
13
|
Liu Z, He X. Painting on programmable reconfigurable metastructures. NATURE MATERIALS 2023; 22:1171-1172. [PMID: 37758976 DOI: 10.1038/s41563-023-01668-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Affiliation(s)
- Zixiao Liu
- Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA, USA
| | - Ximin He
- Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
14
|
Lee YJ, Abdelrahman MK, Kalairaj MS, Ware TH. Self-Assembled Microactuators Using Chiral Liquid Crystal Elastomers. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2302774. [PMID: 37291979 DOI: 10.1002/smll.202302774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/18/2023] [Indexed: 06/10/2023]
Abstract
Materials that undergo reversible changes in form typically require top-down processing to program the microstructure of the material. As a result, it is difficult to program microscale, 3D shape-morphing materials that undergo non-uniaxial deformations. Here, a simple bottom-up fabrication approach to prepare bending microactuators is described. Spontaneous self-assembly of liquid crystal (LC) monomers with controlled chirality within 3D micromold results in a change in molecular orientation across thickness of the microstructure. As a result, heating induces bending in these microactuators. The concentration of chiral dopant is varied to adjust the chirality of the monomer mixture. Liquid crystal elastomer (LCE) microactuators doped with 0.05 wt% of chiral dopant produce needle-shaped actuators that bend from flat to an angle of 27.2 ± 11.3° at 180 °C. Higher concentrations of chiral dopant lead to actuators with reduced bending, and lower concentrations of chiral dopant lead to actuators with poorly controlled bending. Asymmetric molecular alignment inside 3D structure is confirmed by sectioning actuators. Arrays of microactuators that all bend in the same direction can be fabricated if symmetry of geometry of the microstructure is broken. It is envisioned that the new platform to synthesize microstructures can further be applied in soft robotics and biomedical devices.
Collapse
Affiliation(s)
- Yoo Jin Lee
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Mustafa K Abdelrahman
- Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA
| | | | - Taylor H Ware
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
- Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA
| |
Collapse
|
15
|
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: 8] [Impact Index Per Article: 8.0] [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.
Collapse
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
| |
Collapse
|
16
|
Chen M, Gao M, Bai L, Zheng H, Qi HJ, Zhou K. Recent Advances in 4D Printing of Liquid Crystal Elastomers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209566. [PMID: 36461147 DOI: 10.1002/adma.202209566] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/22/2022] [Indexed: 06/09/2023]
Abstract
Liquid crystal elastomers (LCEs) are renowned for their large, reversible, and anisotropic shape change in response to various external stimuli due to their lightly cross-linked polymer networks with an oriented mesogen direction, thus showing great potential for applications in robotics, bio-medics, electronics, optics, and energy. To fully take advantage of the anisotropic stimuli-responsive behaviors of LCEs, it is preferable to achieve a locally controlled mesogen alignment into monodomain orientations. In recent years, the application of 4D printing to LCEs opens new doors for simultaneously programming the mesogen alignment and the 3D geometry, offering more opportunities and higher feasibility for the fabrication of 4D-printed LCE objects with desirable stimuli-responsive properties. Here, the state-of-the-art advances in 4D printing of LCEs are reviewed, with emphasis on both the mechanisms and potential applications. First, the fundamental properties of LCEs and the working principles of the representative 4D printing techniques are briefly introduced. Then, the fabrication of LCEs by 4D printing techniques and the advantages over conventional manufacturing methods are demonstrated. Finally, perspectives on the current challenges and potential development trends toward the 4D printing of LCEs are discussed, which may shed light on future research directions in this new field.
Collapse
Affiliation(s)
- 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
| | - Ming Gao
- 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
| | - Lichun Bai
- School of Traffic and Transportation Engineering, Central South University, Changsha, 410075, China
| | - Han Zheng
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - H 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
| |
Collapse
|
17
|
Zhang P, Debije MG, de Haan LT, Schenning APHJ. Switching between 3D Surface Topographies in Liquid Crystal Elastomer Coatings Using Two-Step Imprint Lithography. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2302051. [PMID: 37189212 DOI: 10.1002/smll.202302051] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/01/2023] [Indexed: 05/17/2023]
Abstract
While dynamic surface topographies are fabricated using liquid crystal (LC) polymers, switching between two distinct 3D topographies remains challenging. In this work, two switchable 3D surface topographies are created in LC elastomer (LCE) coatings using a two-step imprint lithography process. A first imprinting creates a surface microstructure on the LCE coating which is polymerized by a base catalyzed partial thiol-acrylate crosslinking step. The structured coating is then imprinted with a second mold to program the second topography, which is subsequently fully polymerized by light. The resulting LCE coatings display reversible surface switching between the two programmed 3D states. By varying the molds used during the two imprinting steps, diverse dynamic topographies can be achieved. For example, by using grating and rough molds sequentially, switchable surface topographies between a random scatterer and an ordered diffractor are achieved. Additionally, by using negative and positive triangular prism molds consecutively, dynamic surface topographies switching between two 3D structural states are achieved, driven by differential order/disorder transitions in the different areas of the film. It is anticipated that this platform of dynamic 3D topological switching can be used for many applications, including antifouling and biomedical surfaces, switchable friction elements, tunable optics, and beyond.
Collapse
Affiliation(s)
- Pei Zhang
- Stimuli-responsive Functional Materials and Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper, Eindhoven, 5600 MB, The Netherlands
| | - Michael G Debije
- Stimuli-responsive Functional Materials and Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper, Eindhoven, 5600 MB, The Netherlands
- Interactive Polymer Materials (IPM), Eindhoven University of Technology (TU/e), Groene Loper, Eindhoven, 5600 MB, The Netherlands
| | - Laurens T de Haan
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, P. R. China
| | - Albert P H J Schenning
- Stimuli-responsive Functional Materials and Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper, Eindhoven, 5600 MB, The Netherlands
- Interactive Polymer Materials (IPM), Eindhoven University of Technology (TU/e), Groene Loper, Eindhoven, 5600 MB, The Netherlands
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, P. R. China
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology (TU/e), Groene Loper, Eindhoven, 5600 MB, The Netherlands
| |
Collapse
|
18
|
Zhan Y, Broer DJ, Li J, Xue J, Liu D. A cold-responsive liquid crystal elastomer provides visual signals for monitoring a critical temperature decrease. MATERIALS HORIZONS 2023. [PMID: 37098874 DOI: 10.1039/d3mh00271c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Critical temperature indicators have been extensively utilized in various fields, ranging from healthcare to food safety. However, the majority of the temperature indicators are designed for upper critical temperature monitoring, indicating when the temperature rises and exceeds a predefined limit, whereas stringently demanded low critical temperature indicators are scarcely developed. Herein, we develop a new material and system that monitor temperature decrease, e.g., from ambient temperature to the freezing point, or even to an ultra-low temperature of -20 °C. For this purpose, we create a dynamic membrane which can open and close during temperature cycles from high temperature to low temperature. This membrane consists of a gold-liquid crystal elastomer (Au-LCE) bilayer structure. Unlike the commonly used thermo-responsive LCEs which actuate upon temperature rise, our LCE is cold-responsive. This means that geometric deformations occur when the environmental temperature decreases. Specifically, upon temperature decrease the LCE creates stresses at the gold interface by uniaxial deformation due to expansion along the molecular director and shrinkage perpendicular to it. At a critical stress, optimized to occur at the desired temperature, the brittle Au top layer fractures, which allows contact between the LCE and material on top of the gold layer. Material transport via cracks enables the onset of the visible signal for instance caused by a pH indicator substance. We apply the dynamic Au-LCE membrane for cold-chain applications, indicating the loss of the effectiveness of perishable goods. We anticipate that our newly developed low critical temperature/time indicator will be shortly implemented in supply chains to minimize food and medical product waste.
Collapse
Affiliation(s)
- Yuanyuan Zhan
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands.
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands
| | - Dirk J Broer
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands.
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands
| | - Junyu Li
- Molecular Materials and Nanosystems, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands
| | - Jiuzhi Xue
- Smart Liquid Crystal Technologies Co. Ltd, Jiangsu Industrial Technology Research Institute (JITRI), 280 Huangpujiang Road, Chuangshu, 215556, China
| | - Danqing Liu
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands.
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands
| |
Collapse
|
19
|
Liu M, Jin L, Yang S, Wang Y, Murray CB, Yang S. Shape Morphing Directed by Spatially Encoded, Dually Responsive Liquid Crystalline Elastomer Micro-Actuators. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208613. [PMID: 36341507 DOI: 10.1002/adma.202208613] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Liquid crystalline elastomers (LCEs) with intrinsic molecular anisotropy can be programmed to morph shapes under external stimuli. However, it is difficult to program the position and orientation of individual mesogenic units separately and locally, whether in-plane or out-of-plane, since each mesogen is linked to adjacent ones through the covalently bonded polymer chains. Here, dually responsive, spindle-shaped micro-actuators are synthesized from LCE composites, which can reorient under a magnetic field and change the shape upon heating. When the discrete micro-actuators are embedded in a conventional and nonresponsive elastomer with programmed height distribution and in-plane orientation in local regions, robust and complex shape morphing induced by the cooperative actuations of the locally distributed micro-actuators, which corroborates with finite element analysis, are shown. The spatial encoding of discrete micro-actuators in a nonresponsive matrix allows to decouple the actuators and the matrix, broadening the material palette to program local and global responses to stimuli for applications including soft robotics, smart wearables, and sensors.
Collapse
Affiliation(s)
- Mingzhu Liu
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Lishuai Jin
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Shengsong Yang
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yuchen Wang
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Christopher B Murray
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Shu Yang
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| |
Collapse
|
20
|
Rogóż M, Dziekan Z, Dradrach K, Zmyślony M, Nałęcz-Jawecki P, Grabowski P, Fabjanowicz B, Podgórska M, Kudzia A, Wasylczyk P. From Light-Powered Motors, to Micro-Grippers, to Crawling Caterpillars, Snails and Beyond-Light-Responsive Oriented Polymers in Action. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8214. [PMID: 36431699 PMCID: PMC9698796 DOI: 10.3390/ma15228214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/12/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
"How would you build a robot, the size of a bacteria, powered by light, that would swim towards the light source, escape from it, or could be controlled by means of different light colors, intensities or polarizations?" This was the question that Professor Diederik Wiersma asked PW on a sunny spring day in 2012, when they first met at LENS-the European Laboratory of Nonlinear Spectroscopy-in Sesto Fiorentino, just outside Florence in northern Italy. It was not just a vague question, as Prof. Wiersma, then the LENS director and leader of one of its research groups, already had an idea (and an ERC grant) about how to actually make such micro-robots, using a class of light-responsive oriented polymers, liquid crystal elastomers (LCEs), combined with the most advanced fabrication technique-two-photon 3D laser photolithography. Indeed, over the next few years, the LCE technology, successfully married with the so-called direct laser writing at LENS, resulted in a 60 micrometer long walker developed in Prof. Wiersma's group (as, surprisingly, walking at that stage proved to be easier than swimming). After completing his post-doc at LENS, PW returned to his home Faculty of Physics at the University of Warsaw, and started experimenting with LCE, both in micrometer and millimeter scales, in his newly established Photonic Nanostructure Facility. This paper is a review of how the ideas of using light-powered soft actuators in micromechanics and micro-robotics have been evolving in Warsaw over the last decade and what the outcomes have been so far.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Piotr Wasylczyk
- Photonic Nanostructure Facility, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| |
Collapse
|
21
|
Li S, Lerch MM, Waters JT, Deng B, Martens RS, Yao Y, Kim DY, Bertoldi K, Grinthal A, Balazs AC, Aizenberg J. Self-regulated non-reciprocal motions in single-material microstructures. Nature 2022; 605:76-83. [PMID: 35508775 DOI: 10.1038/s41586-022-04561-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/17/2022] [Indexed: 12/29/2022]
Abstract
Living cilia stir, sweep and steer via swirling strokes of complex bending and twisting, paired with distinct reverse arcs1,2. Efforts to mimic such dynamics synthetically rely on multimaterial designs but face limits to programming arbitrary motions or diverse behaviours in one structure3-8. Here we show how diverse, complex, non-reciprocal, stroke-like trajectories emerge in a single-material system through self-regulation. When a micropost composed of photoresponsive liquid crystal elastomer with mesogens aligned oblique to the structure axis is exposed to a static light source, dynamic dances evolve as light initiates a travelling order-to-disorder transition front, transiently turning the structure into a complex evolving bimorph that twists and bends via multilevel opto-chemo-mechanical feedback. As captured by our theoretical model, the travelling front continuously reorients the molecular, geometric and illumination axes relative to each other, yielding pathways composed from series of twisting, bending, photophobic and phototropic motions. Guided by the model, here we choreograph a wide range of trajectories by tailoring parameters, including illumination angle, light intensity, molecular anisotropy, microstructure geometry, temperature and irradiation intervals and duration. We further show how this opto-chemo-mechanical self-regulation serves as a foundation for creating self-organizing deformation patterns in closely spaced microstructure arrays via light-mediated interpost communication, as well as complex motions of jointed microstructures, with broad implications for autonomous multimodal actuators in areas such as soft robotics7,9,10, biomedical devices11,12 and energy transduction materials13, and for fundamental understanding of self-regulated systems14,15.
Collapse
Affiliation(s)
- Shucong Li
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Michael M Lerch
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.,Stratingh Institute for Chemistry, University of Groningen, Groningen, the Netherlands
| | - James T Waters
- Chemical Engineering Department, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bolei Deng
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Reese S Martens
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Yuxing Yao
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Do Yoon Kim
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Katia Bertoldi
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Alison Grinthal
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Anna C Balazs
- Chemical Engineering Department, University of Pittsburgh, Pittsburgh, PA, USA
| | - Joanna Aizenberg
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA. .,John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
| |
Collapse
|
22
|
Sahadevan V, Panigrahi B, Chen CY. Microfluidic Applications of Artificial Cilia: Recent Progress, Demonstration, and Future Perspectives. MICROMACHINES 2022; 13:735. [PMID: 35630202 PMCID: PMC9147031 DOI: 10.3390/mi13050735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/19/2022] [Accepted: 04/19/2022] [Indexed: 02/06/2023]
Abstract
Artificial cilia-based microfluidics is a promising alternative in lab-on-a-chip applications which provides an efficient way to manipulate fluid flow in a microfluidic environment with high precision. Additionally, it can induce favorable local flows toward practical biomedical applications. The endowment of artificial cilia with their anatomy and capabilities such as mixing, pumping, transporting, and sensing lead to advance next-generation applications including precision medicine, digital nanofluidics, and lab-on-chip systems. This review summarizes the importance and significance of the artificial cilia, delineates the recent progress in artificial cilia-based microfluidics toward microfluidic application, and provides future perspectives. The presented knowledge and insights are envisaged to pave the way for innovative advances for the research communities in miniaturization.
Collapse
Affiliation(s)
- Vignesh Sahadevan
- Department of Mechanical Engineering, National Cheng Kung University, Tainan 701, Taiwan;
| | - Bivas Panigrahi
- Department of Refrigeration, Air Conditioning and Energy Engineering, National Chin-Yi University of Technology, Taichung 411, Taiwan;
| | - Chia-Yuan Chen
- Department of Mechanical Engineering, National Cheng Kung University, Tainan 701, Taiwan;
| |
Collapse
|
23
|
Stretchable and self-healable double-network ionogel with strong adhesion and temperature tolerance for information encryption. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118626] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
24
|
van Raak RJH, Broer DJ. Biomimetic Liquid Crystal Cilia and Flagella. Polymers (Basel) 2022; 14:polym14071384. [PMID: 35406258 PMCID: PMC9003437 DOI: 10.3390/polym14071384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 03/25/2022] [Indexed: 02/01/2023] Open
Abstract
Cilia and flagella are a vital part of many organisms. Protozoa such as paramecia rely on the collective and coordinated beating of tubular cilia or flagella for their transport, while mammals depend on the ciliated linings of their bronchia and female reproductive tracts for the continuity of breathing and reproduction, respectively. Over the years, man has attempted to mimic these natural cilia using synthetic materials such as elastomers doped with magnetic particles or light responsive liquid crystal networks. In this review, we will focus on the progress that has been made in mimicking natural cilia and flagella using liquid crystal polymers. We will discuss the progress that has been made in mimicking natural cilia and flagella with liquid crystal polymers using techniques such as fibre drawing, additive manufacturing, or replica moulding, where we will put additional focus on the emergence of asymmetrical and out-of-plane motions.
Collapse
Affiliation(s)
- Roel J. H. van Raak
- Laboratory of Stimuli-Responsive Functional Materials and Devices, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Groene Loper 5, 5612 AE Eindhoven, The Netherlands;
| | - Dirk J. Broer
- Laboratory of Stimuli-Responsive Functional Materials and Devices, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Groene Loper 5, 5612 AE Eindhoven, The Netherlands;
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Groene Loper 5, 5612 AE Eindhoven, The Netherlands
- SCNU-TUE Joint Lab of Devices Integrated Responsive Materials, South China Normal University, Guangzhou Higher Education Mega Center, No. 378, West Waihuan Road, Guangzhou 510006, China
- Correspondence:
| |
Collapse
|
25
|
Ji Y, Yang B, Cai F, Yu H. Regulate Surface Topography of Liquid‐Crystalline Polymer by External Stimuli. MACROMOL CHEM PHYS 2022. [DOI: 10.1002/macp.202100418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yufan Ji
- School of Materials Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Peking University Beijing 100871 P. R. China
| | - Bowen Yang
- School of Materials Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Peking University Beijing 100871 P. R. China
| | - Feng Cai
- School of Materials Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Peking University Beijing 100871 P. R. China
| | - Haifeng Yu
- School of Materials Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Peking University Beijing 100871 P. R. China
| |
Collapse
|
26
|
Astam MO, Zhan Y, Slot TK, Liu D. Active Surfaces Formed in Liquid Crystal Polymer Networks. ACS APPLIED MATERIALS & INTERFACES 2022; 14:22697-22705. [PMID: 35142206 PMCID: PMC9136844 DOI: 10.1021/acsami.1c21024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 02/01/2022] [Indexed: 06/14/2023]
Abstract
There is an increasing interest in animating materials to develop dynamic surfaces. These dynamic surfaces can be utilized for advanced applications, including switchable wetting, friction, and lubrication. Dynamic surfaces can also improve existing technologies, for example, by integrating self-cleaning surfaces on solar cells. In this Spotlight on Applications, we describe our most recent advances in liquid crystal polymer network (LCN) dynamic surfaces, focusing on substrate-based topographies and dynamic porous networks. We discuss our latest insights in the mechanisms of deformation with the "free volume" principle. We illustrate the scope of LCN technology through various examples of photo-/electropatterning, free-volume channeling, oscillating/programmable network distortion, and porous LCNs. Finally, we close by discussing prominent applications of LCNs and their outlook.
Collapse
Affiliation(s)
- Mert O. Astam
- Laboratory
of Stimuli-Responsive Functional Materials and Devices (SFD), Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
- Institute
for Complex Molecular Systems (ICMS), Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
| | - Yuanyuan Zhan
- Laboratory
of Stimuli-Responsive Functional Materials and Devices (SFD), Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
- Institute
for Complex Molecular Systems (ICMS), Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
| | - Thierry K. Slot
- Laboratory
of Stimuli-Responsive Functional Materials and Devices (SFD), Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
- Institute
for Complex Molecular Systems (ICMS), Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
| | - Danqing Liu
- Laboratory
of Stimuli-Responsive Functional Materials and Devices (SFD), Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
- Institute
for Complex Molecular Systems (ICMS), Eindhoven
University of Technology, Groene Loper 3, Eindhoven AE 5612, The Netherlands
- SCNU-TUE
Joint Lab of Device Integrated Responsive Materials (DIRM), National
Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou 510006, P. R. China
| |
Collapse
|
27
|
Jin B, Liu J, Shi Y, Chen G, Zhao Q, Yang S. Solvent-Assisted 4D Programming and Reprogramming of Liquid Crystalline Organogels. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2107855. [PMID: 34808005 DOI: 10.1002/adma.202107855] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/13/2021] [Indexed: 06/13/2023]
Abstract
Encoding molecular ordering during liquid crystalline network (LCN) formation endows preprogrammed but fixed shape morphing in response to external stimuli. The incorporation of dynamic covalent bonds enables shape reprogramming but also permanently alters the network structures. Here, an entropic approach that can program complex shapes via directed solvent evaporation from an isotropic LCN organogel is discoursed. Different shapes can be erased and reprogrammed from the same LCN on demand depending on the modes of deformation of the organogel during solvent evaporation. The ability to decouple network synthesis and molecular alignment relaxes the requirements to LCN chemistry and alignment methods, allowing for the realization of a variety of origami/kirigami structures and 4D shape morphing of LCNs printed from the digital light processing technique with unattainable spatial and temporal controls.
Collapse
Affiliation(s)
- Binjie Jin
- Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA, 19104, USA
- Department of Chemical Engineering and Biological Engineering, Zhejiang University, 38th Zheda Road, Zhejiang, 310027, China
| | - Jiaqi Liu
- Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA, 19104, USA
| | - Yunpeng Shi
- Department of Chemical Engineering and Biological Engineering, Zhejiang University, 38th Zheda Road, Zhejiang, 310027, China
| | - Guancong Chen
- Department of Chemical Engineering and Biological Engineering, Zhejiang University, 38th Zheda Road, Zhejiang, 310027, China
| | - Qian Zhao
- Department of Chemical Engineering and Biological Engineering, Zhejiang University, 38th Zheda Road, Zhejiang, 310027, China
| | - Shu Yang
- Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA, 19104, USA
| |
Collapse
|
28
|
Chen J, Xu Z, Zheng J, Wu H, Chi Y. Phototriggered color modulation of perovskite nanoparticles for high density optical data storage. Chem Sci 2022; 13:10315-10326. [PMID: 36277656 PMCID: PMC9473532 DOI: 10.1039/d2sc02986c] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 08/08/2022] [Indexed: 11/21/2022] Open
Abstract
The perovskite nanocrystals-dichloromethane (PNCs-DCM) with tunable fluorescent color under UV light are a new kind of photoresponsive luminescent materials (PLMs), which are qualified to apply in optical data storage.
Collapse
Affiliation(s)
- Jie Chen
- MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory for Food Safety and Detection, College of Chemistry, Fuzhou University, Fuzhou, 350108, P. R. China
| | - Zelian Xu
- MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory for Food Safety and Detection, College of Chemistry, Fuzhou University, Fuzhou, 350108, P. R. China
| | - Jingcheng Zheng
- MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory for Food Safety and Detection, College of Chemistry, Fuzhou University, Fuzhou, 350108, P. R. China
| | - Haishan Wu
- MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory for Food Safety and Detection, College of Chemistry, Fuzhou University, Fuzhou, 350108, P. R. China
| | - Yuwu Chi
- MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory for Food Safety and Detection, College of Chemistry, Fuzhou University, Fuzhou, 350108, P. R. China
| |
Collapse
|
29
|
Del Pozo M, Sol JAHP, Schenning APHJ, Debije MG. 4D Printing of Liquid Crystals: What's Right for Me? ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2104390. [PMID: 34716625 DOI: 10.1002/adma.202104390] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/20/2021] [Indexed: 05/24/2023]
Abstract
Recent years have seen major advances in the developments of both additive manufacturing concepts and responsive materials. When combined as 4D printing, the process can lead to functional materials and devices for use in health, energy generation, sensing, and soft robots. Among responsive materials, liquid crystals, which can deliver programmed, reversible, rapid responses in both air and underwater, are a prime contender for additive manufacturing, given their ease of use and adaptability to many different applications. In this paper, selected works are compared and analyzed to come to a didactical overview of the liquid crystal-additive manufacturing junction. Reading from front to back gives the reader a comprehensive understanding of the options and challenges in the field, while researchers already experienced in either liquid crystals or additive manufacturing are encouraged to scan through the text to see how they can incorporate additive manufacturing or liquid crystals into their own work. The educational text is closed with proposals for future research in this crossover field.
Collapse
Affiliation(s)
- Marc Del Pozo
- Laboratory for Stimuli-Responsive Functional Materials & Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper 3, Eindhoven, 5612 AE, The Netherlands
| | - Jeroen A H P Sol
- Laboratory for Stimuli-Responsive Functional Materials & Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper 3, Eindhoven, 5612 AE, The Netherlands
| | - Albert P H J Schenning
- Laboratory for Stimuli-Responsive Functional Materials & Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper 3, Eindhoven, 5612 AE, The Netherlands
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Groene Loper 3, Eindhoven, 5612 AE, The Netherlands
| | - Michael G Debije
- Laboratory for Stimuli-Responsive Functional Materials & Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology (TU/e), Groene Loper 3, Eindhoven, 5612 AE, The Netherlands
| |
Collapse
|
30
|
Choi JS, Lim S, Kim J, Chung SS, Moon SE, Im JP, Kim JH, Kang SM. Capillary-Induced Clustering of Thermoresponsive Micropillars. ACS APPLIED MATERIALS & INTERFACES 2021; 13:58201-58208. [PMID: 34817151 DOI: 10.1021/acsami.1c18634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In this study, we demonstrate the controllable clustering of thermoresponsive high-aspect-ratio hydrogel pillars by modulating the elastic modulus of the materials. Generally, high-aspect-ratio polymeric pillars readily cluster owing to the effect of capillary force and adhesion. However, this unstable behavior hinders the implementation of various functionalities such as wetting, adhesion, and energy harvesting on surfaces with such pillars. Conversely, clustering behavior may be required in the case of digital microfluidic platforms that grip tiny particles or perform biological and chemical analyses. Therefore, it is necessary to develop a reliable method for controlling the clustering behavior. To this end, we fabricate high-aspect-ratio pillars that exhibit capillary-induced clustering behavior based on the cross-linker density of the thermoresponsive hydrogel and the temperature of the surrounding environment. Through experimental and theoretical analyses, a criterion for controlling the clustering and recovery behavior of the fabricated pillars is determined. The established criterion is employed to fabricate a smart mobile camera lens cover that can produce blurred and deblurred images based on optical variations resulting from the clustering and recovery of the pillars. The results of this study can be used to fabricate high-aspect-ratio polymeric pillars for use in diverse applications.
Collapse
Affiliation(s)
- Ji Seong Choi
- Department of Mechanical Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Suim Lim
- Department of Mechanical Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Junsoo Kim
- John A. Paulson School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Seong Seok Chung
- Department of Mechanical Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Seung Eon Moon
- Emerging Nano-Materials Research Section, Electronics and Telecommunications Research Institute, Daejeon 305-700, Republic of Korea
| | - Jong Pil Im
- Emerging Nano-Materials Research Section, Electronics and Telecommunications Research Institute, Daejeon 305-700, Republic of Korea
| | - Jeong Hun Kim
- Emerging Nano-Materials Research Section, Electronics and Telecommunications Research Institute, Daejeon 305-700, Republic of Korea
| | - Seong Min Kang
- Department of Mechanical Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| |
Collapse
|
31
|
Carlotti M, Tricinci O, den Hoed F, Palagi S, Mattoli V. Direct laser writing of liquid crystal elastomers oriented by a horizontal electric field. OPEN RESEARCH EUROPE 2021; 1:129. [PMID: 37645193 PMCID: PMC10445945 DOI: 10.12688/openreseurope.14135.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/16/2021] [Indexed: 08/31/2023]
Abstract
Background: The ability to fabricate components capable of performing actuation in a reliable and controlled manner is one of the main research topics in the field of microelectromechanical systems (MEMS). However, the development of these technologies can be limited in many cases by 2D lithographic techniques employed in the fabrication process. Direct Laser Writing (DLW), a 3D microprinting technique based on two-photon polymerization, can offer novel solutions to prepare, both rapidly and reliably, 3D nano- and microstructures of arbitrary complexity. In addition, the use of functional materials in the printing process can result in the fabrication of smart and responsive devices. Methods: In this study, we present a novel methodology for the printing of 3D actuating microelements comprising Liquid Crystal Elastomers (LCEs) obtained by DLW. The alignment of the mesogens was performed using a static electric field (1.7 V/µm) generated by indium-tin oxide (ITO) electrodes patterned directly on the printing substrates. Results: When exposed to a temperature higher than 50°C, the printed microstructures actuated rapidly and reversibly of about 8% in the direction perpendicular to the director. Conclusions: A novel methodology was developed that allows the printing of directional actuators comprising LCEs via DLW. To impart the necessary alignment of the mesogens, a static electric field was applied before the printing process by making use of flat ITO electrodes present on the printing substrates. The resulting microelements showed a reversible change in shape when heated higher than 50 °C.
Collapse
Affiliation(s)
- Marco Carlotti
- Center for Materials Interfaces (CMI), Italian Institute of Technology, Viale Rinaldo Piaggio 34, Pontedera, 56025, Italy
| | - Omar Tricinci
- Center for Materials Interfaces (CMI), Italian Institute of Technology, Viale Rinaldo Piaggio 34, Pontedera, 56025, Italy
| | - Frank den Hoed
- Center for Materials Interfaces (CMI), Italian Institute of Technology, Viale Rinaldo Piaggio 34, Pontedera, 56025, Italy
- Engineering and Technology institute Groningen (ENTEG), University of Groningen, Nijenborgh 4, Groningen, 4747 AG, The Netherlands
| | - Stefano Palagi
- The Biorobotic Institute, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggio 34, Pontedera, 56025, Italy
| | - Virgilio Mattoli
- Center for Materials Interfaces (CMI), Italian Institute of Technology, Viale Rinaldo Piaggio 34, Pontedera, 56025, Italy
| |
Collapse
|
32
|
Ni B, Liu G, Zhang M, Tatoulian M, Keller P, Li MH. Customizable Sophisticated Three-Dimensional Shape Changes of Large-Size Liquid Crystal Elastomer Actuators. ACS APPLIED MATERIALS & INTERFACES 2021; 13:54439-54446. [PMID: 34738782 DOI: 10.1021/acsami.1c18424] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Stimuli-responsive liquid crystal elastomers (LCEs), which exhibit sophisticated and versatile shape variations and functions upon stimulations, have constantly interested material science researchers. To date, many challenges still exist in scaling up orientated LCEs with sophisticated physical shapes and multi-functions. Herein, LCEs with various customizable conventional and exotic three-dimensional (3D) shapes and with sizes larger than those previously reported have been prepared by combining magnetic field alignment and soft lithography technology. These LCEs have film, cylinder, ellipsoid, hemispheroid, tube, pyramid, triangle and rectangle frame, grid pattern, cubic frame, and spring shapes. Meanwhile, diversified deformation behaviors such as contraction, expansion, bending, and twisting have been achieved by effectively controlling the alignment directions. Finally, the LCE actuator with hemispheroid shape has been explored for its possible applications in dynamic Braille displays or lenses with adjustable focal length. The simple strategy reported here provides a convenient way to customize multimorphological large-size 3D LCE actuators and their stimuli-responsive deformations. These systems will considerably enlarge the potential applications of LCEs and benefit the development of LCE soft robots and the future special bionic systems.
Collapse
Affiliation(s)
- Bin Ni
- CNRS, Institut de Recherche de Chimie Paris, UMR8247, Chimie ParisTech, Université Paris Sciences & Lettres, 75005 Paris, France
| | - Gaoyu Liu
- CNRS, Institut de Recherche de Chimie Paris, UMR8247, Chimie ParisTech, Université Paris Sciences & Lettres, 75005 Paris, France
| | - Mengxue Zhang
- CNRS, Institut de Recherche de Chimie Paris, UMR8247, Chimie ParisTech, Université Paris Sciences & Lettres, 75005 Paris, France
| | - Michael Tatoulian
- CNRS, Institut de Recherche de Chimie Paris, UMR8247, Chimie ParisTech, Université Paris Sciences & Lettres, 75005 Paris, France
| | - Patrick Keller
- Institut Curie, Université Paris Sciences & Lettres, CNRS, Sorbonne Université, Laboratoire Physico-Chimie Curie, UMR168, 75005 Paris, France
| | - Min-Hui Li
- CNRS, Institut de Recherche de Chimie Paris, UMR8247, Chimie ParisTech, Université Paris Sciences & Lettres, 75005 Paris, France
| |
Collapse
|
33
|
Wu J, Yao S, Zhang H, Man W, Bai Z, Zhang F, Wang X, Fang D, Zhang Y. Liquid Crystal Elastomer Metamaterials with Giant Biaxial Thermal Shrinkage for Enhancing Skin Regeneration. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2106175. [PMID: 34561930 DOI: 10.1002/adma.202106175] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Indexed: 06/13/2023]
Abstract
Liquid crystal elastomers (LCEs) are a class of soft active materials of increasing interest, because of their excellent actuation and optical performances. While LCEs show biomimetic mechanical properties (e.g., elastic modulus and strength) that can be matched with those of soft biological tissues, their biointegrated applications have been rarely explored, in part, due to their high actuation temperatures (typically above 60 °C) and low biaxial actuation performances (e.g., actuation strain typically below 10%). Here, unique mechanics-guided designs and fabrication schemes of LCE metamaterials are developed that allow access to unprecedented biaxial actuation strain (-53%) and biaxial coefficient of thermal expansion (-33 125 ppm K-1 ), significantly surpassing those (e.g., -20% and -5950 ppm K-1 ) reported previously. A low-temperature synthesis method with use of optimized composition ratios enables LCE metamaterials to offer reasonably high actuation stresses/strains at a substantially reduced actuation temperature (46 °C). Such biocompatible LCE metamaterials are integrated with medical dressing to develop a breathable, shrinkable, hemostatic patch as a means of noninvasive treatment. In vivo animal experiments of skin repair with both round and cross-shaped wounds demonstrate advantages of the hemostatic patch over conventional strategies (e.g., medical dressing and suturing) in accelerating skin regeneration, while avoiding scar and keloid generation.
Collapse
Affiliation(s)
- Jun Wu
- AML, Department of Engineering Mechanics, Center for Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Shenglian Yao
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Hang Zhang
- AML, Department of Engineering Mechanics, Center for Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Weitao Man
- Department of Neurosurgery, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, 102218, P. R. China
| | - Zhili Bai
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Fan Zhang
- AML, Department of Engineering Mechanics, Center for Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Xiumei Wang
- School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, P. R. China
| | - Daining Fang
- Institute of Advanced Structure Technology, Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Yihui Zhang
- AML, Department of Engineering Mechanics, Center for Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| |
Collapse
|
34
|
Li S, Librandi G, Yao Y, Richard AJ, Schneider-Yamamura A, Aizenberg J, Bertoldi K. Controlling Liquid Crystal Orientations for Programmable Anisotropic Transformations in Cellular Microstructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2105024. [PMID: 34473379 DOI: 10.1002/adma.202105024] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Geometric reconfigurations in cellular structures have recently been exploited to realize adaptive materials with applications in mechanics, optics, and electronics. However, the achievable symmetry breakings and corresponding types of deformation and related functionalities have remained rather limited, mostly due to the fact that the macroscopic geometry of the structures is generally co-aligned with the molecular anisotropy of the constituent material. To address this limitation, cellular microstructures are fabricated out of liquid crystalline elastomers (LCEs) with an arbitrary, user-defined liquid crystal (LC) mesogen orientation encrypted by a weak magnetic field. This platform enables anisotropy to be programmed independently at the molecular and structural levels and the realization of unprecedented director-determined symmetry breakings in cellular materials, which are demonstrated by both finite element analyses and experiments. It is illustrated that the resulting mechanical reconfigurations can be harnessed to program microcellular materials with switchable and direction-dependent frictional properties and further exploit "area-specific" deformation patterns to locally modulate transmitted light and precisely guide object movement. As such, the work provides a clear route to decouple anisotropy at the materials level from the directionality of the macroscopic cellular structure, which may lead to a new generation of smart and adaptive materials and devices.
Collapse
Affiliation(s)
- Shucong Li
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Gabriele Librandi
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Yuxing Yao
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Austin J Richard
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Alyssha Schneider-Yamamura
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Joanna Aizenberg
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Katia Bertoldi
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| |
Collapse
|
35
|
Xu Y, Dupont RL, Yao Y, Zhang M, Fang JC, Wang X. Random Liquid Crystalline Copolymers Consisting of Prolate and Oblate Liquid Crystal Monomers. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Yang Xu
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Robert L. Dupont
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yuxing Yao
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Meng Zhang
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jen-Chun Fang
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Xiaoguang Wang
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
- Sustainability Institute, The Ohio State University, Columbus, Ohio 43210, United States
| |
Collapse
|
36
|
Park JE, Won S, Cho W, Kim JG, Jhang S, Lee JG, Wie JJ. Fabrication and applications of stimuli‐responsive micro/nanopillar arrays. JOURNAL OF POLYMER SCIENCE 2021. [DOI: 10.1002/pol.20210311] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jeong Eun Park
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| | - Sukyoung Won
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| | - Woongbi Cho
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| | - Jae Gwang Kim
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| | - Saebohm Jhang
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| | - Jae Gyeong Lee
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| | - Jeong Jae Wie
- Department of Polymer Science and Engineering Inha University Incheon 22212 Republic of Korea
- Program in Environmental and Polymer Engineering Inha University Incheon 22212 Republic of Korea
| |
Collapse
|
37
|
Sun D, Zhang J, Li H, Shi Z, Meng Q, Liu S, Chen J, Liu X. Toward Application of Liquid Crystalline Elastomer for Smart Robotics: State of the Art and Challenges. Polymers (Basel) 2021; 13:1889. [PMID: 34204168 PMCID: PMC8201031 DOI: 10.3390/polym13111889] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 11/17/2022] Open
Abstract
Liquid crystalline elastomers (LCEs) are lightly crosslinked polymers that combine liquid crystalline order and rubber elasticity. Owing to their unique anisotropic behavior and reversible shape responses to external stimulation (temperature, light, etc.), LCEs have emerged as preferred candidates for actuators, artificial muscles, sensors, smart robots, or other intelligent devices. Herein, we discuss the basic action, control mechanisms, phase transitions, and the structure-property correlation of LCEs; this review provides a comprehensive overview of LCEs for applications in actuators and other smart devices. Furthermore, the synthesis and processing of liquid crystal elastomer are briefly discussed, and the current challenges and future opportunities are prospected. With all recent progress pertaining to material design, sophisticated manipulation, and advanced applications presented, a vision for the application of LCEs in the next generation smart robots or automatic action systems is outlined.
Collapse
Affiliation(s)
- Dandan Sun
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| | - Juzhong Zhang
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| | - Hongpeng Li
- School of Mechanical Engineering, Yangzhou University, Yangzhou 225127, China;
| | - Zhengya Shi
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| | - Qi Meng
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| | - Shuiren Liu
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| | - Jinzhou Chen
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| | - Xuying Liu
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China; (D.S.); (Z.S.); (Q.M.); (J.C.); (X.L.)
| |
Collapse
|
38
|
Zhu P, Chen R, Zhou C, Aizenberg M, Aizenberg J, Wang L. Bioinspired Soft Microactuators. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2008558. [PMID: 33860582 DOI: 10.1002/adma.202008558] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/18/2021] [Indexed: 05/28/2023]
Abstract
Soft actuators have the potential of revolutionizing the field of robotics. However, it has been a long-standing challenge to achieve simultaneously: i) miniaturization of soft actuators, ii) high contrast between materials properties at their "on" and "off" states, iii) significant actuation for high-payload mechanical work, and iv) ability to perform diverse shape transformations. This challenge is addressed by synergistically utilizing structural concepts found in the dermis of sea cucumbers and the tendrils of climbing plants, together with microfluidic fabrication to create diatomite-laden hygroscopically responsive fibers with a discontinuous ribbon of stiff, asymmetrically shaped, and hygroscopically inactive microparticles embedded inside. The microactuators can undergo various deformations and have very high property contrast ratios (20-850 for various mechanical characteristics of interest) between hydrated and dehydrated states. The resulting energy density, actuation strain, and actuation stress are shown to exceed those of natural muscle by ≈4, >2, and >30 times, respectively, and their weight-lifting ratio is 2-3 orders of magnitude higher than the value of recent hygroscopic actuators. This work offers a new and general way to design and fabricate next-generation soft microactuators, and thus advances the field of soft robotics by tailoring the structure and properties of deformable elements to suit a desired application.
Collapse
Affiliation(s)
- Pingan Zhu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, China
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
- HKU-Zhejiang Institute of Research and Innovation (HKU-ZIRI), Hangzhou, Zhejiang, 311300, China
| | - Rifei Chen
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, China
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Chunmei Zhou
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, China
- HKU-Zhejiang Institute of Research and Innovation (HKU-ZIRI), Hangzhou, Zhejiang, 311300, China
| | - Michael Aizenberg
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Joanna Aizenberg
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Liqiu Wang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, China
- HKU-Zhejiang Institute of Research and Innovation (HKU-ZIRI), Hangzhou, Zhejiang, 311300, China
| |
Collapse
|
39
|
Liquid-induced topological transformations of cellular microstructures. Nature 2021; 592:386-391. [DOI: 10.1038/s41586-021-03404-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 03/01/2021] [Indexed: 12/21/2022]
|
40
|
Long Rod-Like Liquid Crystal Containing Azobenzene and the Applications in Phase-Transition Regulation and Orientation of Nematic Liquid Crystal. CRYSTALS 2021. [DOI: 10.3390/cryst11040418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Phase-transition and orientation of liquid crystal (LC) are two crucial factors for LC application. In this work, a long rod-like LC compound containing double azobenzene (M1) is successfully designed and synthesized. The combing technologies of nuclear magnetic resonance (1H NMR, 13C NMR) and Fourier transform infrared spectroscopy (FTIR) are used to identify the chemical structure of the molecule. Additionally, the polarized optical microscopy (POM), differential scanning calorimetry (DSC), and one-dimensional wide-angle X-ray diffraction (1D WAXD) experimental results show that M1 exhibits an ultrawide range of LC phases and a stable LC structure even at ultrahigh temperature, which indicates that this LC can be applied in some especial devices. Further, the compound M1 is used to tune the LC temperature range of the commercial LC 4-cyano-4′-pentylbiphenyl (5CB). A series of samples 1–7 are obtained through doping different contents of M1, which show different LC temperature ranges that are dependent on the composition ratio of M1 and 5CB. More interestingly, all resultant samples show spontaneous vertical orientation on the hydrophilic glass substrate. Meanwhile, due to the effect of azobenzene in the compound M1, a reversible transition between homeotropic to random orientation of the LC molecules is achieved when these LC cells are alternately exposed to UV irradiation and visible light, which implies that this material shows potential application in especial display and optical storage technologies.
Collapse
|
41
|
Ni K, Peng Q, Gao E, Wang K, Shao Q, Huang H, Xue L, Wang Z. Core-Shell Magnetic Micropillars for Reprogrammable Actuation. ACS NANO 2021; 15:4747-4758. [PMID: 33617237 DOI: 10.1021/acsnano.0c09298] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Stimuli-responsive micro/nanostructures that exhibit not only programmable but also reprogrammable actuation behaviors are highly desirable for various advanced engineering applications (e.g., anticounterfeiting, information encoding, dynamic imaging and display, microrobotics, etc.) but yet to be realized with state-of-the-art technologies. Here we report a concept and a corresponding experimental technique for core-shell magnetic micropillars enabling simultaneously programmable and reprogrammable actuations using a simple magnetic field. The micropillars are composed of elastomeric hollow shells for shaping encapsulated with liquid magnetic nanocomposite resin cores for actuating. The spatial distribution of the magnetic nanoparticles inside the resin channels can be dynamically modulated within individual micropillars, which consequently regulates the magnetomechanical responses of the pillars upon actuation (bending deformation varied near 1 order of magnitude under the same actuation field). We demonstrate that the micropillars with contrasting bending responses can be configured in an arbitrary spatial pattern by direct magnetic writing, and the written pattern can then be easily magnetically erased to facilitate next-round rewriting and reconfiguration. This reprogrammable actuation capability of the micropillars is further demonstrated by their potential applications for rewritable paper and recyclable displays, where various microscale characteristics can be controlled to dynamically appear and disappear at the same or different locations of one single micropillar array. The core-shell magnetic micropillars reported here provide a universal prototype for reprogrammable responsive micro/nanostructures through rational design and facile fabrication from conventional materials.
Collapse
Affiliation(s)
- Ke Ni
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China
| | - Qi Peng
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China
| | - Enlai Gao
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China
| | - Kun Wang
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China
| | - Qian Shao
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China
| | - Houbing Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
| | - Longjian Xue
- School of Power and Mechanical Engineering, The Institute of Technological Science, Wuhan University, Wuhan, Hubei 430072, China
| | - Zhengzhi Wang
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China
| |
Collapse
|
42
|
Multiple hydrogen-bonded cross-linked photo-responsive liquid crystal elastomers with photo-responsive fluorescence. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123420] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
43
|
Zhang J, Guo Y, Hu W, Soon RH, Davidson ZS, Sitti M. Liquid Crystal Elastomer-Based Magnetic Composite Films for Reconfigurable Shape-Morphing Soft Miniature Machines. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2006191. [PMID: 33448077 PMCID: PMC7610459 DOI: 10.1002/adma.202006191] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/30/2020] [Indexed: 05/08/2023]
Abstract
Stimuli-responsive and active materials promise radical advances for many applications. In particular, soft magnetic materials offer precise, fast, and wireless actuation together with versatile functionality, while liquid crystal elastomers (LCEs) are capable of large reversible and programmable shape-morphing with high work densities in response to various environmental stimuli, e.g., temperature, light, and chemical solutions. Integrating the orthogonal stimuli-responsiveness of these two kinds of active materials could potentially enable new functionalities and future applications. Here, magnetic microparticles (MMPs) are embedded into an LCE film to take the respective advantages of both materials without compromising their independent stimuli-responsiveness. This composite material enables reconfigurable magnetic soft miniature machines that can self-adapt to a changing environment. In particular, a miniature soft robot that can autonomously alter its locomotion mode when it moves from air to hot liquid, a vine-like filament that can sense and twine around a support, and a light-switchable magnetic spring are demonstrated. The integration of LCEs and MMPs into monolithic structures introduces a new dimension in the design of soft machines and thus greatly enhances their use in applications in complex environments, especially for miniature soft robots, which are self-adaptable to environmental changes while being remotely controllable.
Collapse
Affiliation(s)
- Jiachen Zhang
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
| | - Yubing Guo
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
| | - Wenqi Hu
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
| | - Ren Hao Soon
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
| | - Zoey S. Davidson
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
| | - Metin Sitti
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
- Department of Information Technology and Electrical EngineeringETH ZürichZürich8092Switzerland
| |
Collapse
|
44
|
Lu X, Ambulo CP, Wang S, Rivera‐Tarazona LK, Kim H, Searles K, Ware TH. 4D‐Printing of Photoswitchable Actuators. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202012618] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Xili Lu
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
- Current address: State Key Laboratory of Polymer Materials Engineering Polymer Research Institute Sichuan University Chengdu 610065 China
| | - Cedric P. Ambulo
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
| | - Suitu Wang
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
- Current address: Department of Materials Science and Engineering Texas A&M University College Station TX 77843 USA
| | - Laura K. Rivera‐Tarazona
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
- Current address: Department of Biomedical Engineering Texas A&M University College Station TX 77843 USA
| | - Hyun Kim
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
- Current address: Sensors and Electron Devices Directorate CCDC Army Research Laboratory Adelphi MD 20783 USA
| | - Kyle Searles
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
| | - Taylor H. Ware
- Department of Bioengineering University of Texas at Dallas Richardson TX 75080 USA
- Current address: Department of Biomedical Engineering Texas A&M University College Station TX 77843 USA
- Current address: Department of Materials Science and Engineering Texas A&M University College Station TX 77843 USA
| |
Collapse
|
45
|
Lu X, Ambulo CP, Wang S, Rivera-Tarazona LK, Kim H, Searles K, Ware TH. 4D-Printing of Photoswitchable Actuators. Angew Chem Int Ed Engl 2021; 60:5536-5543. [PMID: 33217118 DOI: 10.1002/anie.202012618] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/02/2020] [Indexed: 12/15/2022]
Abstract
Shape-switching behavior, where a transient stimulus induces an indefinitely stable deformation that can be recovered on exposure to another transient stimulus, is critical to building smart structures from responsive polymers as continue power is not needed to maintain deformations. Herein, we 4D-print shape-switching liquid crystalline elastomers (LCEs) functionalized with supramolecular crosslinks, dynamic covalent crosslinks, and azobenzene. The salient property of shape-switching LCEs is that light induces long-lived, deformation that can be recovered on-demand by heating. UV-light isomerizes azobenzene from trans to cis, and temporarily breaks the supramolecular crosslinks, resulting in a programmed deformation. After UV, the shape-switching LCEs fix more than 90 % of the deformation over 3 days by the reformed supramolecular crosslinks. Using the shape-switching properties, we print Braille-like actuators that can be photoswitched to display different letters. This new class of photoswitchable actuators may impact applications such as deployable devices where continuous application of power is impractical.
Collapse
Affiliation(s)
- Xili Lu
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA.,Current address: State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu, 610065, China
| | - Cedric P Ambulo
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Suitu Wang
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA.,Current address: Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Laura K Rivera-Tarazona
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA.,Current address: Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Hyun Kim
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA.,Current address: Sensors and Electron Devices Directorate, CCDC Army Research Laboratory, Adelphi, MD, 20783, USA
| | - Kyle Searles
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Taylor H Ware
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA.,Current address: Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA.,Current address: Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA
| |
Collapse
|
46
|
Ambulo CP, Tasmim S, Wang S, Abdelrahman MK, Zimmern PE, Ware TH. Processing advances in liquid crystal elastomers provide a path to biomedical applications. JOURNAL OF APPLIED PHYSICS 2020; 128:140901. [PMID: 33060862 PMCID: PMC7546753 DOI: 10.1063/5.0021143] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/24/2020] [Indexed: 05/08/2023]
Abstract
Liquid crystal elastomers (LCEs) are a class of stimuli-responsive polymers that undergo reversible shape-change in response to environmental changes. The shape change of LCEs can be programmed during processing by orienting the liquid crystal phase prior to crosslinking. The suite of processing techniques that has been developed has resulted in a myriad of LCEs with different shape-changing behavior and mechanical properties. Aligning LCEs via mechanical straining yields large uniaxial actuators capable of a moderate force output. Magnetic fields are utilized to control the alignment within LCE microstructures. The generation of out-of-plane deformations such as bending, twisting, and coning is enabled by surface alignment techniques within thin films. 4D printing processes have emerged that enable the fabrication of centimeter-scale, 3D LCE structures with a complex alignment. The processing technique also determines, to a large extent, the potential applications of the LCE. For example, 4D printing enables the fabrication of LCE actuators capable of replicating the forces generated by human muscles. Employing surface alignment techniques, LCE films can be designed for use as coatings or as substrates for stretchable electronics. The growth of new processes and strategies opens and strengthens the path for LCEs to be applicable within biomedical device designs.
Collapse
Affiliation(s)
- Cedric P Ambulo
- Department of Bioengineering, The University of Texas at Dallas, Richardson, Texas 75080, USA
| | | | | | | | - Philippe E Zimmern
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | | |
Collapse
|
47
|
Guo Y, Shahsavan H, Sitti M. 3D Microstructures of Liquid Crystal Networks with Programmed Voxelated Director Fields. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2002753. [PMID: 32767434 PMCID: PMC7610484 DOI: 10.1002/adma.202002753] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/03/2020] [Indexed: 05/17/2023]
Abstract
The shape-shifting behavior of liquid crystal networks (LCNs) and elastomers (LCEs) is a result of an interplay between their initial geometrical shape and their molecular alignment. For years, reliance on either one-step in situ or two-step film processing techniques has limited the shape-change transformations from 2D to 3D geometries. The combination of various fabrication techniques, alignment methods, and chemical formulations developed in recent years has introduced new opportunities to achieve 3D-to-3D shape-transformations in large scales, albeit the precise control of local molecular alignment in microscale 3D constructs remains a challenge. Here, the voxel-by-voxel encoding of nematic alignment in 3D microstructures of LCNs produced by two-photon polymerization using high-resolution topographical features is demonstrated. 3D LCN microstructures (suspended films, coils, and rings) with designable 2D and 3D director fields with a resolution of 5 µm are achieved. Different shape transformations of LCN microstructures with the same geometry but dissimilar molecular alignments upon actuation are elicited. This strategy offers higher freedom in the shape-change programming of 3D LCN microstructures and expands their applicability in emerging technologies, such as small-scale soft robots and devices and responsive surfaces.
Collapse
Affiliation(s)
- Yubing Guo
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Hamed Shahsavan
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany; Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Metin Sitti
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| |
Collapse
|
48
|
Zmyślony M, Dradrach K, Haberko J, Nałęcz-Jawecki P, Rogóż M, Wasylczyk P. Optical Pliers: Micrometer-Scale, Light-Driven Tools Grown on Optical Fibers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2002779. [PMID: 32627876 DOI: 10.1002/adma.202002779] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/21/2020] [Indexed: 06/11/2023]
Abstract
The ability to grip and handle small objects, from sub-millimeter electronic components to single-micrometer living cells, is vital for numerous ever-shrinking technologies. Mechanical grippers, powered by electric, pneumatic, hydraulic or piezoelectric servos, are well suited for the job at larger scales, but their complexity and need for force transmission prevent their miniaturization and remote control in tight spaces. Using liquid crystal elastomer microstructures that can change shape quickly and reversibly in response to light, a light-powered gripping tool-optical pliers-is built by growing two bending jaws on the tips of optical fibers. By delivering UV light to trigger polymerization via a micrometer-size fiber core, structures of similar size can be made without resorting to any microfabrication technology, such as laser photolithography. The tool is operated using visible light energy supplied through the fibers, with no force transmission. The elastomer growth technique readily offers micrometer-scale, remotely controlled functional structures with different modes of actuation as building blocks for the microtoolbox.
Collapse
Affiliation(s)
- Michał Zmyślony
- Photonic Nanostructure Facility, Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw, 02-093, Poland
| | - Klaudia Dradrach
- Photonic Nanostructure Facility, Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw, 02-093, Poland
| | - Jakub Haberko
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, Kraków, 30-059, Poland
| | - Paweł Nałęcz-Jawecki
- Photonic Nanostructure Facility, Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw, 02-093, Poland
| | - Mikołaj Rogóż
- Photonic Nanostructure Facility, Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw, 02-093, Poland
| | - Piotr Wasylczyk
- Photonic Nanostructure Facility, Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw, 02-093, Poland
| |
Collapse
|
49
|
Wang Z, Wang K, Liang D, Yan L, Ni K, Huang H, Li B, Guo Z, Wang J, Ma X, Tang X, Chen LQ. Hybrid Magnetic Micropillar Arrays for Programmable Actuation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2001879. [PMID: 32406075 DOI: 10.1002/adma.202001879] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/17/2020] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Stimuli-responsive micro/nanostructures that can dynamically and reversibly adapt their configurations according to external stimuli have stimulated a wide scope of engineering applications, ranging from material surface engineering to micromanipulations. However, it remains a challenge to achieve a precise local control of the actuation to realize applications that require heterogeneous and on-demand responses. Here, a new experimental technique is developed for large arrays of hybrid magnetic micropillars and achieve precise local control of actuation using a simple magnetic field. By manipulating the spatial distribution of magnetic nanoparticles within individual elastomer micropillars, a wide range of the magnetomechanical responses from less than 5% to ≈50% for the ratio of the bending deflection to the original length of the pillars is realized. It is demonstrated that the micropillars with different degrees of bending deformation can be configured in any spatial pattern using a photomask-assisted template-casting technique to achieve heterogeneous, site-specific, and programmed bending actuations. This unprecedented local control of the micropillars offers exciting novel applications, as demonstrated here in encryptable surface printing and stamping, direction- and track-programmable microparticle/droplet transport, and smart magnetic micro-tweezers. The hybrid magnetic micropillars reported here provide a versatile prototype for heterogeneous and on-demand actuation using programmable stimuli-responsive micro/nanostructures.
Collapse
Affiliation(s)
- Zhengzhi Wang
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei, 430072, China
| | - Kun Wang
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei, 430072, China
| | - Deshan Liang
- Department of Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Linhai Yan
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei, 430072, China
| | - Ke Ni
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei, 430072, China
| | - Houbing Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Bei Li
- School of Materials Science and Engineering, Wuhan University of Technology, Wuhan, Hubei, 430070, China
| | - Zhiwei Guo
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, Hubei, 430072, China
| | - Junsheng Wang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Xingqiao Ma
- Department of Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xuhai Tang
- Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei, 430072, China
| | - Long-Qing Chen
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| |
Collapse
|
50
|
Jeon J, Park JE, Park SJ, Won S, Zhao H, Kim S, Shim BS, Urbas A, Hart AJ, Ku Z, Wie JJ. Shape-Programmed Fabrication and Actuation of Magnetically Active Micropost Arrays. ACS APPLIED MATERIALS & INTERFACES 2020; 12:17113-17120. [PMID: 32134249 DOI: 10.1021/acsami.0c01511] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Micro- and nanotextured surfaces with reconfigurable textures can enable advancements in the control of wetting and heat transfer, directed assembly of complex materials, and reconfigurable optics, among many applications. However, reliable and programmable directional shape in large scale is significant for prescribed applications. Herein, we demonstrate the self-directed fabrication and actuation of large-area elastomer micropillar arrays, using magnetic fields to both program a shape-directed actuation response and rapidly and reversibly actuate the arrays. Specifically, alignment of magnetic microparticles during casting of micropost arrays with hemicylindrical shapes imparts a deterministic anisotropy that can be exploited to achieve the prescribed, large-deformation bending or twisting of the pillars. The actuation coincides with the finite element method, and we demonstrate reversible, noncontact magnetic actuation of arrays of tens of thousands of pillars over hundreds of cycles, with the bending and twisting angles of up to 72 and 61°, respectively. Moreover, we demonstrate the use of the surfaces to control anisotropic liquid spreading and show that the capillary self-assembly of actuated micropost arrays enables highly complex architectures to be fabricated. The present technique could be scaled to indefinite areas using cost-effective materials and casting techniques, and the principle of shape-directed pillar actuation can be applied to other active material systems.
Collapse
Affiliation(s)
- Jisoo Jeon
- Department of Polymer Science and Engineering, Inha University, Incheon 22212, South Korea
| | - Jeong Eun Park
- Department of Polymer Science and Engineering, Inha University, Incheon 22212, South Korea
| | - Sei Jin Park
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Sukyoung Won
- Department of Polymer Science and Engineering, Inha University, Incheon 22212, South Korea
| | - Hangbo Zhao
- Department of Mechanical Engineering and Laboratory for Manufacturing and Productivity, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Sanha Kim
- Department of Mechanical Engineering and Laboratory for Manufacturing and Productivity, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Bong Sup Shim
- Department of Chemical Engineering, Inha University, Incheon 22212, South Korea
| | - Augustine Urbas
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - A John Hart
- Department of Mechanical Engineering and Laboratory for Manufacturing and Productivity, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Zahyun Ku
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Jeong Jae Wie
- Department of Polymer Science and Engineering, Inha University, Incheon 22212, South Korea
| |
Collapse
|