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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.
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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
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Song Q, Chen Y, Hou P, Zhu P, Helmer D, Kotz-Helmer F, Rapp BE. Fabrication of Multi-Material Pneumatic Actuators and Microactuators Using Stereolithography. MICROMACHINES 2023; 14:244. [PMID: 36837944 PMCID: PMC9966499 DOI: 10.3390/mi14020244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Pneumatic actuators are of great interest for device miniaturization, microactuators, soft robots, biomedical engineering, and complex control systems. Recently, multi-material actuators have become of high interest to researchers due to their comprehensive range of suitable applications. Three-dimensional (3D) printing of multi-material pneumatic actuators would be the ideal way to fabricate customized actuators, but so far, this is mostly limited to deposition-based methodologies, such as fused deposition modeling (FDM) or Polyjetting. Vat-based stereolithography is one of the most relevant high-resolution 3D printing methods but is only rarely utilized in the multi-material 3D printing of materials. This study demonstrated multi-material stereolithography using combinations of materials with different Young's moduli, i.e., 0.5 MPa and 1.1 GPa, for manufacturing pneumatic actuators and microactuators with a resolution as small as 200 μm. These multi-material actuators have advantages over single-material actuators in terms of their deformation controllability and ease of assembly.
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Affiliation(s)
- Qingchuan Song
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
- FIT Freiburg Center of Interactive Materials and Bioinspired Technologies, University of Freiburg, 79110 Freiburg, Germany
| | - Yunong Chen
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Peilong Hou
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Pang Zhu
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Dorothea Helmer
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
- FIT Freiburg Center of Interactive Materials and Bioinspired Technologies, University of Freiburg, 79110 Freiburg, Germany
- Glassomer GmbH, In den Kirchenmatten 54, 79110 Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, 79104 Freiburg, Germany
| | - Frederik Kotz-Helmer
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
- FIT Freiburg Center of Interactive Materials and Bioinspired Technologies, University of Freiburg, 79110 Freiburg, Germany
- Glassomer GmbH, In den Kirchenmatten 54, 79110 Freiburg, Germany
| | - Bastian E. Rapp
- Laboratory of Process Technology, NeptunLab, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
- FIT Freiburg Center of Interactive Materials and Bioinspired Technologies, University of Freiburg, 79110 Freiburg, Germany
- Glassomer GmbH, In den Kirchenmatten 54, 79110 Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, 79104 Freiburg, Germany
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Song X, Zhang W, Liu H, Zhao L, Chen Q, Tian H. 3D printing of liquid crystal elastomers-based actuator for an inchworm-inspired crawling soft robot. Front Robot AI 2022; 9:889848. [PMID: 36035870 PMCID: PMC9399622 DOI: 10.3389/frobt.2022.889848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 07/13/2022] [Indexed: 11/24/2022] Open
Abstract
Liquid crystal elastomers (LCEs) have shown great potential as soft actuating materials in soft robots, with large actuation strain and fast response speed. However, to achieve the unique features of actuation, the liquid crystal mesogens should be well aligned and permanently fixed by polymer networks, limiting their practical applications. The recent progress in the 3D printing technologies of LCEs overcame the shortcomings in conventional processing techniques. In this study, the relationship between the 3D printing parameters and the actuation performance of LCEs is studied in detail. Furthermore, a type of inchworm-inspired crawling soft robot based on a liquid crystal elastomeric actuator is demonstrated, coupled with tilted fish-scale-like microstructures with anisotropic friction as the foot for moving forwards. In addition, the anisotropic friction of inclined scales with different angles is measured to demonstrate the performance of anisotropic friction. Lastly, the kinematic performance of the inchworm-inspired robot is tested on different surfaces.
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Guan Z, Wang L, Bae J. Advances in 4D printing of liquid crystalline elastomers: materials, techniques, and applications. MATERIALS HORIZONS 2022; 9:1825-1849. [PMID: 35504034 DOI: 10.1039/d2mh00232a] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Liquid crystalline elastomers (LCEs) are polymer networks exhibiting anisotropic liquid crystallinity while maintaining elastomeric properties. Owing to diverse polymeric forms and self-alignment molecular behaviors, LCEs have fascinated state-of-the-art efforts in various disciplines other than the traditional low-molar-mass display market. By patterning order to structures, LCEs demonstrate reversible high-speed and large-scale actuations in response to external stimuli, allowing for close integration with 4D printing and architectures of digital devices, which is scarcely observed in homogeneous soft polymer networks. In this review, we collect recent advances in 4D printing of LCEs, with emphases on synthesis and processing methods that enable microscopic changes in the molecular orientation and hence macroscopic changes in the properties of end-use objects. Promising potentials of printed complexes include fields of soft robotics, optics, and biomedical devices. Within this scope, we elucidate the relationships among external stimuli, tailorable morphologies in mesophases of liquid crystals, and programmable topological configurations of printed parts. Lastly, perspectives and potential challenges facing 4D printing of LCEs are discussed.
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Affiliation(s)
- Zhecun Guan
- Department of Nanoengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Ling Wang
- School of Materials Science and Engineering, Tianjin University, Tianjin 300350, P. R. China.
| | - Jinhye Bae
- Department of Nanoengineering, University of California San Diego, La Jolla, CA 92093, USA.
- Chemical Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
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Wang W, Zhang Y, Zhang YL, Zhang JR, Sun XC, Han DD, Sun HB. Multicoating Nanoarchitectonics for Facile Preparation of Multi-Responsive Paper Actuators. ACS APPLIED MATERIALS & INTERFACES 2022; 14:27242-27250. [PMID: 35657172 DOI: 10.1021/acsami.2c06048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Stimuli-responsive actuators (SRAs) that can harvest environmental energies and convert them to mechanical works without additional energy-supplying systems have revealed great potential for robotic applications. However, at present, the practical usage of SRAs is significantly limited due to the problems with respect to solo responsiveness, simple deformation, and the difficulties for large-scale and cost-effective production. In this paper, multi-responsive paper actuators with multicoating nanoarchitectonics that enable complex deformation have been fabricated through a very simple painting process on common papers. The resultant paper actuator permits large-scale and low-cost production (A4 size: ∼0.5 dollar). The paper actuators that consist of a paper/graphite/polydimethylsiloxane sandwich structure can be actuated by multi-form stimuli, including moisture, temperature, light, and volatile organic compounds. More importantly, the bending deformation of the paper actuators can be further programmed by controlling the pencil drawing orientation, providing the feasibility of performing more complex deformations. Several multi-responsive paper actuators, including organic compound-responsive smart devices working in the liquid environment, moisture-enabled terrestrial crawling actuator, and a light-responsive attitude-control actuator integrated with an airplane model, have been demonstrated. The development of multi-responsive yet cost-effective paper actuators may hold great promise for a wide range of practical applications, for instance, soft micro-electromechanical systems, lab-on-a-chip systems, smart homes, and robotics.
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Affiliation(s)
- Wei Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin Province 130012, China
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications, Nanjing, Jiangsu Province 210023, China
| | - Yang Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, Jilin Province 130021, China
| | - Yong-Lai Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin Province 130012, China
| | - Jia-Rui Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin Province 130012, China
| | - Xiang-Chao Sun
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin Province 130012, China
| | - Dong-Dong Han
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin Province 130012, China
| | - Hong-Bo Sun
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin Province 130012, China
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Haidian, Beijing 10084, China
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Lugger SJ, Houben SJA, Foelen Y, Debije MG, Schenning APHJ, Mulder DJ. Hydrogen-Bonded Supramolecular Liquid Crystal Polymers: Smart Materials with Stimuli-Responsive, Self-Healing, and Recyclable Properties. Chem Rev 2022; 122:4946-4975. [PMID: 34428022 PMCID: PMC8915167 DOI: 10.1021/acs.chemrev.1c00330] [Citation(s) in RCA: 83] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Indexed: 01/18/2023]
Abstract
Hydrogen-bonded liquid crystalline polymers have emerged as promising "smart" supramolecular functional materials with stimuli-responsive, self-healing, and recyclable properties. The hydrogen bonds can either be used as chemically responsive (i.e., pH-responsive) or as dynamic structural (i.e., temperature-responsive) moieties. Responsiveness can be manifested as changes in shape, color, or porosity and as selective binding. The liquid crystalline self-organization gives the materials their unique responsive nanostructures. Typically, the materials used for actuators or optical materials are constructed using linear calamitic (rod-shaped) hydrogen-bonded complexes, while nanoporous materials are constructed from either calamitic or discotic (disk-shaped) complexes. The dynamic structural character of the hydrogen bond moieties can be used to construct self-healing and recyclable supramolecular materials. In this review, recent findings are summarized, and potential future applications are discussed.
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Affiliation(s)
- Sean J.
D. Lugger
- Stimuli-responsive
Functional Materials and Devices, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
| | - Simon J. A. Houben
- Stimuli-responsive
Functional Materials and Devices, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
| | - Yari Foelen
- Stimuli-responsive
Functional Materials and Devices, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
| | - Michael G. Debije
- Stimuli-responsive
Functional Materials and Devices, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
| | - Albert P. H. J. Schenning
- Stimuli-responsive
Functional Materials and Devices, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
- SCNU-TUE
Joint Laboratory of Device Integrated Responsive Materials (DIRM), South China Normal University, Guangzhou Higher Education Mega Center, 510006 Guangzhou, China
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, Den Dolech 2, 5600 MB, Eindhoven, The Netherlands
| | - Dirk J. Mulder
- Stimuli-responsive
Functional Materials and Devices, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
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7
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Leveille M, Shen X, Fu W, Jin K, Acerce M, Wang C, Bustamante J, Casas AM, Feng Y, Ge N, Hirst LS, Ghosh S, Lu JQ. Directional, Low-Energy Driven Thermal Actuating Bilayer Enabled by Coordinated Submolecular Switching. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102077. [PMID: 34687166 PMCID: PMC8655216 DOI: 10.1002/advs.202102077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/29/2021] [Indexed: 05/29/2023]
Abstract
The authors reveal a thermal actuating bilayer that undergoes reversible deformation in response to low-energy thermal stimuli, for example, a few degrees of temperature increase. It is made of an aligned carbon nanotube (CNT) sheet covalently connected to a polymer layer in which dibenzocycloocta-1,5-diene (DBCOD) actuating units are oriented parallel to CNTs. Upon exposure to low-energy thermal stimulation, coordinated submolecular-level conformational changes of DBCODs result in macroscopic thermal contraction. This unique thermal contraction offers distinct advantages. It's inherently fast, repeatable, low-energy driven, and medium independent. The covalent interface and reversible nature of the conformational change bestow this bilayer with excellent repeatability, up to at least 70 000 cycles. Unlike conventional CNT bilayer systems, this system can achieve high precision actuation readily and can be scaled down to nanoscale. A new platform made of poly(vinylidene fluoride) (PVDF) in tandem with the bilayer can harvest low-grade thermal energy and convert it into electricity. The platform produces 86 times greater energy than PVDF alone upon exposure to 6 °C thermal fluctuations above room temperature. This platform provides a pathway to low-grade thermal energy harvesting. It also enables low-energy driven thermal artificial robotics, ultrasensitive thermal sensors, and remote controlled near infrared (NIR) driven actuators.
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Affiliation(s)
| | - Xinyuan Shen
- Materials Science and EngineeringUniversity of California, MercedMerced95343USA
- Macromolecular ScienceFudan UniversityShanghai200433P. R. China
| | - Wenxin Fu
- Materials Science and EngineeringUniversity of California, MercedMerced95343USA
| | - Ke Jin
- Macromolecular ScienceFudan UniversityShanghai200433P. R. China
| | - Muharrem Acerce
- Materials Science and EngineeringUniversity of California, MercedMerced95343USA
| | - Changchun Wang
- Macromolecular ScienceFudan UniversityShanghai200433P. R. China
| | | | | | - Yuan Feng
- ChemistryUniversity of California, IrvineIrvine92697USA
| | - Nien‐Hui Ge
- ChemistryUniversity of California, IrvineIrvine92697USA
| | | | | | - Jennifer Qing Lu
- PhysicsUniversity of California, MercedMerced95343USA
- Materials Science and EngineeringUniversity of California, MercedMerced95343USA
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Kim K, Guo Y, Bae J, Choi S, Song HY, Park S, Hyun K, Ahn SK. 4D Printing of Hygroscopic Liquid Crystal Elastomer Actuators. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2100910. [PMID: 33938152 DOI: 10.1002/smll.202100910] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/16/2021] [Indexed: 06/12/2023]
Abstract
Liquid crystal elastomers (LCEs) are broadly recognized as programmable actuating materials that are responsive to external stimuli, typically heat or light. Yet, soft LCEs that respond to changes in environmental humidity are not reported, except a few examples based on rigid liquid crystal networks with limited processing. Herein, a new class of highly deformable hygroscopic LCE actuators that can be prepared by versatile processing methods, including surface alignment as well as 3D printing is presented. The dimethylamino-functionalized LCE is prepared by the aza-Michael addition reaction between a reactive LC monomer and N,N'-dimethylethylenediamine as a chain extender, followed by photopolymerization. The humidity-responsive properties are introduced by activating one of the LCE surfaces with an acidic solution, which generates cations on the surface and provides asymmetric hydrophilicity to the LCE. The resulting humidity-responsive LCE undergoes programmed and reversible hygroscopic actuation, and its shape transformation can be directed by the cut angle with respect to a nematic director or by localizing activation regions in the LCE. Most importantly, various hygroscopic LCE actuators, including (porous) bilayers, a flower, a concentric square array, and a soft gripper, are successfully fabricated by using LC inks in UV-assisted direct-ink-writing-based 3D printing.
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Affiliation(s)
- Keumbee Kim
- Department of Polymer Science and Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Yuanhang Guo
- Department of Polymer Science and Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Jaehee Bae
- Department of Polymer Science and Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Subi Choi
- Department of Polymer Science and Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Hyeong Yong Song
- Institute for Environment and Energy, Pusan National University, Busan, 46241, Republic of Korea
- School of Chemical Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Sungmin Park
- Advanced Materials Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea
| | - Kyu Hyun
- School of Chemical Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Suk-Kyun Ahn
- Department of Polymer Science and Engineering, Pusan National University, Busan, 46241, Republic of Korea
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Lavrentovich OD. Design of nematic liquid crystals to control microscale dynamics. LIQUID CRYSTALS REVIEWS 2021; 8:59-129. [PMID: 34956738 PMCID: PMC8698256 DOI: 10.1080/21680396.2021.1919576] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/11/2021] [Indexed: 05/25/2023]
Abstract
The dynamics of small particles, both living such as swimming bacteria and inanimate, such as colloidal spheres, has fascinated scientists for centuries. If one could learn how to control and streamline their chaotic motion, that would open technological opportunities in the transformation of stored or environmental energy into systematic motion, with applications in micro-robotics, transport of matter, guided morphogenesis. This review presents an approach to command microscale dynamics by replacing an isotropic medium with a liquid crystal. Orientational order and associated properties, such as elasticity, surface anchoring, and bulk anisotropy, enable new dynamic effects, ranging from the appearance and propagation of particle-like solitary waves to self-locomotion of an active droplet. By using photoalignment, the liquid crystal can be patterned into predesigned structures. In the presence of the electric field, these patterns enable the transport of solid and fluid particles through nonlinear electrokinetics rooted in anisotropy of conductivity and permittivity. Director patterns command the dynamics of swimming bacteria, guiding their trajectories, polarity of swimming, and distribution in space. This guidance is of a higher level of complexity than a simple following of the director by rod-like microorganisms. Namely, the director gradients mediate hydrodynamic interactions of bacteria to produce an active force and collective polar modes of swimming. The patterned director could also be engraved in a liquid crystal elastomer. When an elastomer coating is activated by heat or light, these patterns produce a deterministic surface topography. The director gradients define an activation force that shapes the elastomer in a manner similar to the active stresses triggering flows in active nematics. The patterned elastomer substrates could be used to define the orientation of cells in living tissues. The liquid-crystal guidance holds a major promise in achieving the goal of commanding microscale active flows.
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Affiliation(s)
- Oleg D Lavrentovich
- Advanced Materials and Liquid Crystal Institute, Department of Physics, Materials Science Graduate Program, Kent State University, Kent, OH 44242, USA
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Verpaalen RC, Engels T, Schenning APHJ, Debije MG. Stimuli-Responsive Shape Changing Commodity Polymer Composites and Bilayers. ACS APPLIED MATERIALS & INTERFACES 2020; 12:38829-38844. [PMID: 32805900 PMCID: PMC7472435 DOI: 10.1021/acsami.0c10802] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Commodity polymers are produced in large volumes, providing robust mechanical properties at relatively low costs. The products made from these commodity polymers typically offer only static functionalities. Over the past decade, however, in the scientific literature, stimuli-responsive additives and/or polymer coatings have been introduced to commodity polymers, yielding composites and bilayers that change shape in response to light, temperature, and/or humidity. These stimuli responsive commodity polymers allow the marketing and sales of these otherwise bulk products as "high-end" smart materials for applications spanning from soft actuators to adaptive textiles. This Spotlight on Applications presents an overview of recent intriguing works on how shape changing commodity polymer composite and bilayer actuators based on polyamide 6, poly(ethylene terephthalate), polyethylene, and polypropylene have been fabricated that respond to environmental stimuli and discusses their potential applications.
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Affiliation(s)
- Rob C.
P. Verpaalen
- Laboratory
of Stimuli-Responsive Functional Materials and Devices, Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, Den Dolech 2, 5600 MB Eindhoven, The Netherlands
| | - Tom Engels
- DSM
Material Science Center, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
- Department
of Mechanical Engineering, Materials Technology Institute, Polymer
Technology Group, Eindhoven University of
Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Albert P. H. J. Schenning
- Laboratory
of Stimuli-Responsive Functional Materials and Devices, Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, Den Dolech 2, 5600 MB Eindhoven, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, Den Dolech 2, 5600 MB, Eindhoven, The Netherlands
| | - Michael G. Debije
- Laboratory
of Stimuli-Responsive Functional Materials and Devices, Department
of Chemical Engineering and Chemistry, Eindhoven
University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, Den Dolech 2, 5600 MB Eindhoven, The Netherlands
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