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van Hazendonk L, Khalil ZJ, van Grondelle W, Wijkhuijs LEA, Schreur-Piet I, Debije MG, Friedrich H. Hot Fingers: Individually Addressable Graphene-Heater Actuated Liquid Crystal Grippers. ACS APPLIED MATERIALS & INTERFACES 2024; 16:32739-32747. [PMID: 38869014 PMCID: PMC11212024 DOI: 10.1021/acsami.4c06130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/23/2024] [Accepted: 06/03/2024] [Indexed: 06/14/2024]
Abstract
Liquid crystal-based actuators are receiving increased attention for their applications in wearables and biomedical or surgical devices, with selective actuation of individual parts/fingers still being in its infancy. This work presents the design and realization of two gripper devices with four individually addressable liquid-crystal network (LCN) actuators thermally driven via printed graphene-based heating elements. The resistive heat causes the all-organic actuator to bend due to anisotropic volume expansions of the splay-aligned sample. A heat transfer model that includes all relevant interfaces is presented and verified via thermal imaging, which provides good estimates of dimensions, power production, and resistance required to reach the desired temperature for actuation while maintaining safe electrical potentials. The LCN films displace up to 11 mm with a bending force of 1.10 mN upon application of 0-15 V potentials. The robustness of the LCN finger is confirmed by repetitive on/off switching for 500 cycles. Actuators are assembled into two prototypes able to grip and lift objects of small weights (70-100 mg) and perform complex actions by individually controlling one of the device's fingers to grip an additional object. Selective actuation of parts in soft robotic devices will enable more complex motions and actions to be performed.
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Affiliation(s)
- Laura
S. van Hazendonk
- Laboratory
of Physical Chemistry, Department of Chemical
Engineering and Chemistry Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
| | - Zafeiris J. Khalil
- Laboratory
of Physical Chemistry, Department of Chemical
Engineering and Chemistry Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
| | - Wilko van Grondelle
- Laboratory
of Physical Chemistry, Department of Chemical
Engineering and Chemistry Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
| | - Levina E. A. Wijkhuijs
- Laboratory
of Physical Chemistry, Department of Chemical
Engineering and Chemistry Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
| | - Ingeborg Schreur-Piet
- Laboratory
of Physical Chemistry, Department of Chemical
Engineering and Chemistry Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
- Center
for Multiscale Electron Microscopy, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
| | - Michael G. Debije
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
- Stimuli-responsive
Functional Materials and Devices (SFD), Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
| | - Heiner Friedrich
- Laboratory
of Physical Chemistry, Department of Chemical
Engineering and Chemistry Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
- Institute
for Complex Molecular Systems, Eindhoven
University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
- Center
for Multiscale Electron Microscopy, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, P.O. box 513, Eindhoven 5600 MB, The Netherlands
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2
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McCracken JM, Donovan BR, White TJ. Materials as Machines. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1906564. [PMID: 32133704 DOI: 10.1002/adma.201906564] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/19/2019] [Indexed: 05/23/2023]
Abstract
Machines are systems that harness input power to extend or advance function. Fundamentally, machines are based on the integration of materials with mechanisms to accomplish tasks-such as generating motion or lifting an object. An emerging research paradigm is the design, synthesis, and integration of responsive materials within or as machines. Herein, a particular focus is the integration of responsive materials to enable robotic (machine) functions such as gripping, lifting, or motility (walking, crawling, swimming, and flying). Key functional considerations of responsive materials in machine implementations are response time, cyclability (frequency and ruggedness), sizing, payload capacity, amenability to mechanical programming, performance in extreme environments, and autonomy. This review summarizes the material transformation mechanisms, mechanical design, and robotic integration of responsive materials including shape memory alloys (SMAs), piezoelectrics, dielectric elastomer actuators (DEAs), ionic electroactive polymers (IEAPs), pneumatics and hydraulics systems, shape memory polymers (SMPs), hydrogels, and liquid crystalline elastomers (LCEs) and networks (LCNs). Structural and geometrical fabrication of these materials as wires, coils, films, tubes, cones, unimorphs, bimorphs, and printed elements enables differentiated mechanical responses and consistently enables and extends functional use.
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Affiliation(s)
- Joselle M McCracken
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Brian R Donovan
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Timothy J White
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO, 80309, USA
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3
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Piezoelectric materials as stimulatory biomedical materials and scaffolds for bone repair. Acta Biomater 2018; 73:1-20. [PMID: 29673838 DOI: 10.1016/j.actbio.2018.04.026] [Citation(s) in RCA: 144] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/19/2018] [Accepted: 04/15/2018] [Indexed: 12/14/2022]
Abstract
The process of bone repair and regeneration requires multiple physiological cues including biochemical, electrical and mechanical - that act together to ensure functional recovery. Myriad materials have been explored as bioactive scaffolds to deliver these cues locally to the damage site, amongst these piezoelectric materials have demonstrated significant potential for tissue engineering and regeneration, especially for bone repair. Piezoelectric materials have been widely explored for power generation and harvesting, structural health monitoring, and use in biomedical devices. They have the ability to deform with physiological movements and consequently deliver electrical stimulation to cells or damaged tissue without the need of an external power source. Bone itself is piezoelectric and the charges/potentials it generates in response to mechanical activity are capable of enhancing bone growth. Piezoelectric materials are capable of stimulating the physiological electrical microenvironment, and can play a vital role to stimulate regeneration and repair. This review gives an overview of the association of piezoelectric effect with bone repair, and focuses on state-of-the-art piezoelectric materials (polymers, ceramics and their composites), the fabrication routes to produce piezoelectric scaffolds, and their application in bone repair. Important characteristics of these materials from the perspective of bone tissue engineering are highlighted. Promising upcoming strategies and new piezoelectric materials for this application are presented. STATEMENT OF SIGNIFICANCE Electrical stimulation/electrical microenvironment are known effect the process of bone regeneration by altering the cellular response and are crucial in maintaining tissue functionality. Piezoelectric materials, owing to their capability of generating charges/potentials in response to mechanical deformations, have displayed great potential for fabricating smart stimulatory scaffolds for bone tissue engineering. The growing interest of the scientific community and compelling results of the published research articles has been the motivation of this review article. This article summarizes the significant progress in the field with a focus on the fabrication aspects of piezoelectric materials. The review of both material and cellular aspects on this topic ensures that this paper appeals to both material scientists and tissue engineers.
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Guin T, Kowalski BA, Rao R, Auguste AD, Grabowski CA, Lloyd PF, Tondiglia VP, Maruyama B, Vaia RA, White TJ. Electrical Control of Shape in Voxelated Liquid Crystalline Polymer Nanocomposites. ACS APPLIED MATERIALS & INTERFACES 2018; 10:1187-1194. [PMID: 29239172 DOI: 10.1021/acsami.7b13814] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Liquid crystal elastomers (LCEs) exhibit anisotropic mechanical, thermal, and optical properties. The director orientation within an LCE can be spatially localized into voxels [three-dimensional (3-D) volume elements] via photoalignment surfaces. Here, we prepare nanocomposites in which both the orientation of the LCE and single-walled carbon nanotube (SWNT) are locally and arbitrarily oriented in discrete voxels. The addition of SWNTs increases the stiffness of the LCE in the orientation direction, yielding a material with a 5:1 directional modulus contrast. The inclusion of SWNT modifies the thermomechanical response and, most notably, is shown to enable distinctive electromechanical deformation of the nanocomposite. Specifically, the incorporation of SWNTs sensitizes the LCE to a dc field, enabling uniaxial electrostriction along the orientation direction. We demonstrate that localized orientation of the LCE and SWNT allows complex 3-D shape transformations to be electrically triggered. Initial experiments indicate that the SWNT-polymer interfaces play a crucial role in enabling the electrostriction reported herein.
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Affiliation(s)
- Tyler Guin
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
- Azimuth Corporation , 4027 Colonel Glenn Highway, Beavercreek, Ohio 45431, United States
| | - Benjamin A Kowalski
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
- Azimuth Corporation , 4027 Colonel Glenn Highway, Beavercreek, Ohio 45431, United States
| | - Rahul Rao
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
| | - Anesia D Auguste
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
| | - Christopher A Grabowski
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
- UES, Inc. , 4401 Dayton Xenia Rd, Beavercreek, Ohio 45432, United States
| | - Pamela F Lloyd
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
- UES, Inc. , 4401 Dayton Xenia Rd, Beavercreek, Ohio 45432, United States
| | - Vincent P Tondiglia
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
- Azimuth Corporation , 4027 Colonel Glenn Highway, Beavercreek, Ohio 45431, United States
| | - Benji Maruyama
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
| | - Richard A Vaia
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
| | - Timothy J White
- Air Force Research Laboratory, Materials and Manufacturing Directorate , 3005 Hobson Way, Wright-Patterson AFB, Ohio 45433-7750, United States
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Wang T, Farajollahi M, Choi YS, Lin IT, Marshall JE, Thompson NM, Kar-Narayan S, Madden JDW, Smoukov SK. Electroactive polymers for sensing. Interface Focus 2016; 6:20160026. [PMID: 27499846 PMCID: PMC4918837 DOI: 10.1098/rsfs.2016.0026] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Electromechanical coupling in electroactive polymers (EAPs) has been widely applied for actuation and is also being increasingly investigated for sensing chemical and mechanical stimuli. EAPs are a unique class of materials, with low-moduli high-strain capabilities and the ability to conform to surfaces of different shapes. These features make them attractive for applications such as wearable sensors and interfacing with soft tissues. Here, we review the major types of EAPs and their sensing mechanisms. These are divided into two classes depending on the main type of charge carrier: ionic EAPs (such as conducting polymers and ionic polymer–metal composites) and electronic EAPs (such as dielectric elastomers, liquid-crystal polymers and piezoelectric polymers). This review is intended to serve as an introduction to the mechanisms of these materials and as a first step in material selection for both researchers and designers of flexible/bendable devices, biocompatible sensors or even robotic tactile sensing units.
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Affiliation(s)
- Tiesheng Wang
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK; EPSRC Centre for Doctoral Training in Sensor Technologies and Applications, University of Cambridge, Cambridge CB2 3RA, UK
| | - Meisam Farajollahi
- Advanced Materials and Process Engineering Laboratory , University of British Columbia , Vancouver, British Columbia , Canada V6T 1Z4
| | - Yeon Sik Choi
- Department of Materials Science and Metallurgy , University of Cambridge , Cambridge CB3 0FS , UK
| | - I-Ting Lin
- Department of Materials Science and Metallurgy , University of Cambridge , Cambridge CB3 0FS , UK
| | - Jean E Marshall
- Department of Materials Science and Metallurgy , University of Cambridge , Cambridge CB3 0FS , UK
| | - Noel M Thompson
- Department of Materials Science and Metallurgy , University of Cambridge , Cambridge CB3 0FS , UK
| | - Sohini Kar-Narayan
- Department of Materials Science and Metallurgy , University of Cambridge , Cambridge CB3 0FS , UK
| | - John D W Madden
- Advanced Materials and Process Engineering Laboratory , University of British Columbia , Vancouver, British Columbia , Canada V6T 1Z4
| | - Stoyan K Smoukov
- Department of Materials Science and Metallurgy , University of Cambridge , Cambridge CB3 0FS , UK
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Na YH, Aburaya Y, Orihara H, Hiraoka K, Han Y. Electrically induced deformation in chiral smectic elastomers with different domain structures. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:062507. [PMID: 25615119 DOI: 10.1103/physreve.90.062507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Indexed: 06/04/2023]
Abstract
Electrical actuation is investigated in two kinds of chiral smectic liquid-crystal elastomers (LCEs) with different domain structures LCE1 and LCE2: The latter is better than the former in orientational order. Tracking fluorescent beads dispersed on the samples enables us to measure the two-dimensional strain tensors in ferroelectric elastomer films. It turns out that the electric-field-induced strain is polarity dependent and the type of molecular orientation responsible for the strain is specified. In LCE1 the shear strain is dominant, whereas in LCE2 it is comparable to the elongation strain, which is explained by the rotation of the principal axes. The essential differences of the two elastomers are observed in the eigenvalues of the strain tensors. The absolute values for LCE1 are larger than those for LCE2. The difference is discussed on the basis of the domain structures.
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Affiliation(s)
- Yang Ho Na
- Department of Advanced Materials, Hannam University, Jeonmin-dong 461-6, Yuseong-gu, Daejeon 305-811, Korea
| | - Yuki Aburaya
- Division of Applied Physics, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo 060-8628, Japan
| | - Hiroshi Orihara
- Division of Applied Physics, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo 060-8628, Japan
| | - Kazuyuki Hiraoka
- Department of Life Science & Sustainable Chemistry, Tokyo Polytechnic University, 1583 Iiyama, Atsugi 243-0297, Japan
| | - Youngbae Han
- Department of Mechanical and Design Engineering, Hongik University, Sejong-ro 2639, Jochiwon-eup, Sejong 339-701, Korea
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7
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García-Márquez AR, Heinrich B, Beyer N, Guillon D, Donnio B. Mesomorphism and Shape-Memory Behavior of Main-Chain Liquid-Crystalline Co-Elastomers: Modulation by the Chemical Composition. Macromolecules 2014. [DOI: 10.1021/ma501164u] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Alfonso Ramon García-Márquez
- Institut
de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 (CNRS-Université de Strasbourg), 23 Rue du Loess BP 43, 67034 Strasbourg, Cedex 2, France
| | - Benoît Heinrich
- Institut
de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 (CNRS-Université de Strasbourg), 23 Rue du Loess BP 43, 67034 Strasbourg, Cedex 2, France
| | - Nicolas Beyer
- Institut
de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 (CNRS-Université de Strasbourg), 23 Rue du Loess BP 43, 67034 Strasbourg, Cedex 2, France
| | - Daniel Guillon
- Institut
de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 (CNRS-Université de Strasbourg), 23 Rue du Loess BP 43, 67034 Strasbourg, Cedex 2, France
| | - Bertrand Donnio
- Institut
de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 (CNRS-Université de Strasbourg), 23 Rue du Loess BP 43, 67034 Strasbourg, Cedex 2, France
- Complex Assemblies
of Soft Matter Laboratory (COMPASS), UMI 3254 (CNRS-Solvay-University
of Pennsylvania), CRTB, 350 George
Patterson Boulevard, Bristol, Pennsylvania 19007, United States
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8
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Chen H, Yu Z, Hedden RC. Influence of thermal history on mesoscale ordering in polydomain smectic networks. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/polb.23207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Liang D, Zhou LJ, Zhang Q, Chen F, Wang K, Deng H, Fu Q. Morphology and mechanical properties of poly(ethyleneoctene) copolymers obtained by dynamic packing injection molding. CHINESE JOURNAL OF POLYMER SCIENCE 2012. [DOI: 10.1007/s10118-012-1159-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Jia YG, Hu JS, Li D, Meng QB, Zhang X. Synthesis and phase behavior of chiral liquid crystalline polymeric networks derived from menthol. HIGH PERFORM POLYM 2012. [DOI: 10.1177/0954008312449843] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The synthesis of new chiral monomer 4-(menthyloxyacetoxy- benzoyloxy)biphenyl-4′-(2-(undec-10-e noyloxy)ethoxy)benzoate (ML), crosslinking agent 4-(undec-10-enoyloxy)biphenyl-4′-(2-(undec-10-enoyloxy)ethoxy)benzoate (CA), and liquid crystal polymer networks (E1−E5) containing menthyl group is presented. Their chemical structures and phase behavior were characterized with Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H-NMR), elemental analyses, polarizing optical microscopy, differential scanning calorimetry, thermogravimetric analysis (TGA), and X-ray diffraction. The selective reflection of light for ML was investigated with ultraviolet/visible/near infrared (UV/Visible/NIR). By inserting a flexible spacer between the mesogenic core and the terminal menthyl groups, MLcould form mesophase and show a chiral smectic C phase, cholesteric phase and cubic blue phase. CA displayed a smectic A phase and nematic phase. The polymer networks containing less than 12 mol% of the crosslinking units showed reversible cholesteric phase transition, wide mesophase temperature range, and excellent thermal stability. With increasing the content of crosslinking unit, the corresponding Tg increased, the Ti decreased, and the mesophase temperature range narrowed for E1−E5. TGA showed that the Td(5%) was greater than 330°C for E1−E5.
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Affiliation(s)
| | - Jian-She Hu
- Center for Molecular Science and Engineering, College of Science, Northeastern University, Shenyang, China
| | - Dan Li
- Northeastern University, Shenyang, China
| | | | - Xia Zhang
- Northeastern University, Shenyang, China
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12
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Applications of Liquid Crystalline Elastomers. LIQUID CRYSTAL ELASTOMERS: MATERIALS AND APPLICATIONS 2012. [DOI: 10.1007/12_2011_164] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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13
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Brown AW, Adams JM. Negative Poisson's ratio and semisoft elasticity of smectic-C liquid-crystal elastomers. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:011703. [PMID: 22400579 DOI: 10.1103/physreve.85.011703] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 12/09/2011] [Indexed: 05/31/2023]
Abstract
Models of smectic-C liquid-crystal elastomers predict that they can display soft elasticity, in which the shape of the elastomer changes at no energy cost. The amplitude of the soft mode and the accompanying shears are dependent on the orientation of the layer normal and the director with respect to the stretch axis. We demonstrate that in some geometries the director is forced to rotate perpendicular to the stretch axis, causing lateral expansion of the sample-a negative Poisson's ratio. Current models do not include the effect of imperfections that must be present in the physical sample. We investigate the effect of a simple model of these imperfections on the soft modes in monodomain smectic-C elastomers in a variety of geometries. When stretching parallel to the layer normal (with imposed strain) the elastomer has a negative stiffness once the director starts to rotate. We show that this is a result of the negative Poisson's ratio in this geometry through a simple scalar model.
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Affiliation(s)
- A W Brown
- SEPnet and the Department of Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom
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14
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Na YH, Aburaya Y, Orihara H, Hiraoka K. Measurement of electrically induced shear strain in a chiral smectic liquid-crystal elastomer. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:061709. [PMID: 21797389 DOI: 10.1103/physreve.83.061709] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 05/13/2011] [Indexed: 05/31/2023]
Abstract
The mechanical response to electrical stimulation was investigated in a chiral smectic elastomer. The two-dimensional strain tensor in an elastomer film was precisely measured by tracking fluorescent beads dispersed on the film. Shear deformation in the film was clearly observed when an electric field was applied perpendicular to the film surface. The temperature dependence of the strain tensor was also investigated, and the origin of the electric-field-induced shear strain in the chiral smectic-C phase was mainly attributed to the Nambu-Goldstone mode.
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Affiliation(s)
- Yang Ho Na
- Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Kita-ku, Sapporo, Japan
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15
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Sánchez-Ferrer A, Finkelmann H. Polydomain-Monodomain Orientational Process in Smectic-C Main-Chain Liquid-Crystalline Elastomers. Macromol Rapid Commun 2010; 32:309-15. [DOI: 10.1002/marc.201000590] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Revised: 10/02/2010] [Indexed: 11/11/2022]
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