51
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Wang Y, Liu Q, Zhang J, Hong T, Sun W, Tang L, Arnold E, Suo Z, Hong W, Ren Z, Guo CF. Giant Poisson's Effect for Wrinkle-Free Stretchable Transparent Electrodes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1902955. [PMID: 31268581 DOI: 10.1002/adma.201902955] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/10/2019] [Indexed: 06/09/2023]
Abstract
The next generation of flexible electronics will require highly stretchable and transparent electrodes, many of which consist of a relatively stiff metal network (or carbon materials) and an underlying soft substrate. Typically, such a stiff-soft bilayer suffers from wrinkling or folding when subjected to strains, causing high surface roughness and seriously deteriorated optical transparency. In this work, a network with a giant effective Poisson's ratio on a soft substrate is found to be under biaxial tension upon deformation, and thus does not wrinkle or fold, but maintains smooth surfaces and high transparency. Soft tactile sensors employing such network electrodes exhibit high transparency and low fatigue over many stretching cycles. Such a giant Poisson's ratio has the same effect in other systems. This work offers a new understanding of surface instabilities and a general strategy to prevent them not only in flexible electronics, but also in other materials and mechanical structures that require flat surfaces.
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Affiliation(s)
- Yan Wang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
- Centers for Mechanical Engineering Research and Education at MIT and SUSTech, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Qihan Liu
- School of Engineering and Applied Sciences, Kavli Institute for Nanobio Science and Technology, Harvard University, Cambridge, MA, 02138, USA
| | - Jianming Zhang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
- Centers for Mechanical Engineering Research and Education at MIT and SUSTech, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Tianzeng Hong
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Wenting Sun
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Lu Tang
- Department of Physics and TcSUH, University of Houston, TX, 77204, USA
| | - Eric Arnold
- Burdette Keeland Jr. Design Exploration Center, College of Architecture and Design, University of Houston, TX, 77204, USA
| | - Zhigang Suo
- School of Engineering and Applied Sciences, Kavli Institute for Nanobio Science and Technology, Harvard University, Cambridge, MA, 02138, USA
| | - Wei Hong
- Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Zhifeng Ren
- Department of Physics and TcSUH, University of Houston, TX, 77204, USA
| | - Chuan Fei Guo
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
- Centers for Mechanical Engineering Research and Education at MIT and SUSTech, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
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52
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Deng B, Mo C, Tournat V, Bertoldi K, Raney JR. Focusing and Mode Separation of Elastic Vector Solitons in a 2D Soft Mechanical Metamaterial. PHYSICAL REVIEW LETTERS 2019; 123:024101. [PMID: 31386527 DOI: 10.1103/physrevlett.123.024101] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Indexed: 06/10/2023]
Abstract
Soft mechanical metamaterials can support a rich set of dynamic responses, which, to date, have received relatively little attention. Here, we report experimental, numerical, and analytical results describing the behavior of an anisotropic two-dimensional flexible mechanical metamaterial when subjected to impact loading. We not only observe the propagation of elastic vector solitons with three components-two translational and one rotational-that are coupled together, but also very rich direction-dependent behaviors such as the formation of sound bullets and the separation of pulses into different solitary modes.
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Affiliation(s)
- Bolei Deng
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Chengyang Mo
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Vincent Tournat
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
- Laboratoire d'Acoustique de l'Université du Mans, LAUM - UMR 6613 CNRS, Le Mans Université, France
| | - Katia Bertoldi
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
- Kavli Institute, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Jordan R Raney
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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53
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Zhou LY, Gao Q, Fu JZ, Chen QY, Zhu JP, Sun Y, He Y. Multimaterial 3D Printing of Highly Stretchable Silicone Elastomers. ACS APPLIED MATERIALS & INTERFACES 2019; 11:23573-23583. [PMID: 31184459 DOI: 10.1021/acsami.9b04873] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
3D printing of silicone elastomers with the direct ink writing (DIW) process has demonstrated great potential in areas as diverse as flexible electronics, medical devices, and soft robotics. However, most of current silicones are not printable because of their low viscosity and long curing time. The lack of systematic research on materials, devices, and processes during printing makes it a huge challenge to apply the DIW process more deeply and widely. In this report, aiming at the dilemmas in materials, devices, and processes, we proposed a comprehensive guide for printing highly stretchable silicone. Specifically, to improve the printability of silicone elastomers, nanosilica was added as a rheology modifier without sacrificing any stretching ability. To effectively control print speed and accuracy, a theoretical model was built and verified. With this strategy, silicone elastomers with different mechanical properties can all be printed and can realize infinite time and high speed printing (>25 mm/s) while maintaining accuracy. Here, super-stretchable silicone that can be stretched to 2000% was printed for the first time, and complex structures can be printed with high quality. For further demonstration, prosthetic nose, data glove capable of detecting fingers' movement, and artificial muscle that can lift objects were printed directly. We believe that this work could provide a guide for further work using the DIW process to print soft matters in a wide range of application scenarios.
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Affiliation(s)
| | | | | | | | - Jia-Pei Zhu
- State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body , Changsha 410082 , China
| | | | - Yong He
- Key Laboratory of Materials Processing and Mold, Ministry of Education , Zhengzhou University , Zhengzhou 450002 , China
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54
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Lei M, Hong W, Zhao Z, Hamel C, Chen M, Lu H, Qi HJ. 3D Printing of Auxetic Metamaterials with Digitally Reprogrammable Shape. ACS APPLIED MATERIALS & INTERFACES 2019; 11:22768-22776. [PMID: 31140776 DOI: 10.1021/acsami.9b06081] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Two-dimensional lattice structures with specific geometric features have been reported to have a negative Poisson's ratio, termed as auxetic metamaterials, that is, stretching-induced expansion in the transversal direction. In this paper, we designed a novel auxetic metamaterial; by utilizing the shape memory effect of the constituent materials, the in-plane moduli and Poisson's ratios can be continuously tailored. During deformation, the curved meshes ensure the rotation of the mesh joints to achieve auxetics. The rotations of these mesh joints are governed by the mesh curvature, which continuously changes during deformation. Because of the shape memory effect, the mesh curvature after printing can be programmed, which can be used to tune the rotation of the mesh joints and the mechanical properties of auxetic metamaterial structures, including Poisson's ratios, moduli, and fracture strains. Using the finite element method, the deformation of these auxetic meshes was analyzed. Finally, we designed and fabricated gradient/digital patterns and cylindrical shells and used the auxetics and shape memory effects to reshape the printed structures.
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Affiliation(s)
- Ming Lei
- State Key Laboratory of Science and Technology on Advanced Composites in Special Environments , Harbin Institute of Technology , Harbin 150080 , P. R. China
- The George W. Woodruff School of Mechanical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Wei Hong
- State Key Laboratory of Science and Technology on Advanced Composites in Special Environments , Harbin Institute of Technology , Harbin 150080 , P. R. China
| | - Zeang Zhao
- The George W. Woodruff School of Mechanical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Craig Hamel
- The George W. Woodruff School of Mechanical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Mingji Chen
- Institute of Advanced Structure Technology , Beijing Institute of Technology , Beijing 100081 , P. R. China
| | - Haibao Lu
- State Key Laboratory of Science and Technology on Advanced Composites in Special Environments , Harbin Institute of Technology , Harbin 150080 , P. R. China
| | - H Jerry Qi
- The George W. Woodruff School of Mechanical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
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55
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Li J, Kong T, Yu J, Lee KH, Tang YH, Kwok KW, Kim JT, Shum HC. Electrocoiling-guided printing of multiscale architectures at single-wavelength resolution. LAB ON A CHIP 2019; 19:1953-1960. [PMID: 31044199 DOI: 10.1039/c9lc00145j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The rope coiling observed in liquid ink with high viscosity has been exploited in additive printing to fabricate architectures with periodically curled structures and tune their mechanical properties. However, the control over the coiling path relying on mechanical motion restricts the spatiotemporal resolution. We develop an electrically assisted high-resolution technique to manipulate coiling paths of viscous ink and structures of the deposited filament. By spatially programming the voltage applied onto the viscous ink, we show that the switching between different filament structures can be accomplished at single wavelength resolution, facilitating the rapid and accurate construction of sophisticated patterns. Furthermore, translational guiding of the electrocoiling enables rapid printing of filaments with complex structures at a line speed of 102 mm s-1. With a simplified trajectory of the printing head, large-area and multiscale patterns can be printed at an unprecedented speed; for instance, centimeter-sized architectures constructed from nanofibers with micron-sized curled structures can be completed in a few minutes. By enabling the printing of complex fiber networks with tunable shape and density, our work provides a route towards custom-design of fiber architectures with unique features such as spatially varying mechanical properties.
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Affiliation(s)
- Jingmei Li
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong. and HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, China
| | - Tiantian Kong
- China Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Shenzhen University, 518037, China
| | - Jiazuo Yu
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong.
| | - Kit Hang Lee
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong.
| | - Yuk Heng Tang
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong. and HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, China
| | - Ka-Wai Kwok
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong.
| | - Ji Tae Kim
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, 999077, Hong Kong. and HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, China
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56
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Ling S, Kang W, Tao S, Zhang C. Highly concentrated graphene oxide ink for facile 3D printing of supercapacitors. NANO MATERIALS SCIENCE 2019. [DOI: 10.1016/j.nanoms.2019.05.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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57
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Wang J, Yang S, Ding P, Cao X, Zhang Y, Cao S, Zhang K, Kong S, Zhou Y, Wang X, Li D, Kong D. Omnidirectional Printing of Soft Elastomer for Liquid-State Stretchable Electronics. ACS APPLIED MATERIALS & INTERFACES 2019; 11:18590-18598. [PMID: 31050403 DOI: 10.1021/acsami.9b04730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Stretchable electronics has emerged as a new class of electronic technology to expand the applications of conventional electronics built on rigid wafers. Among various systems, liquid-state devices utilize electronically active liquids to achieve excellent stretchability and durability. The widespread adaption to such attractive form of device is hindered by the lack of robust fabrication approach to precisely and efficiently assemble liquid-state materials into functional systems. In this study, an additive manufacturing platform for digital fabrication of three-dimensional elastomeric structures is reported. The shear-thinning ink is formulated to enable omnidirectional printing process. Various elastic features with complex architectures are generated without using sacrificial materials, which consist of overhanging parts, suspended structures, and embedded channels. Harnessing the unique printability allows facile creation of elastomeric sensors with strain- and pressure-sensing capabilities by simply filling the embedded microchannels with liquid metal. A smart glove to capture hand gestures is also demonstrated as a fully integrated electronic system with liquid-state components. The liquid-state stretchable electronics developed here may find potential applications in biomedical instruments, wearable devices, and soft robotics.
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Affiliation(s)
- Jiachen Wang
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
| | - Sennan Yang
- College of Chemical Engineering and Technology, Engineering Research Center of Seawater Utilization Technology of Ministry of Education, State Key Laboratory of Reliability and Intelligence of Electrical Equipment , Hebei University of Technology , Tianjin 300130 , China
| | - Peitao Ding
- Key Laboratory of High Performance Polymer Materials and Technology of Ministry of Education, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China
| | - Xiangyu Cao
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
| | - Yue Zhang
- Key Laboratory of High Performance Polymer Materials and Technology of Ministry of Education, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China
| | - Shitai Cao
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
| | - Kuikui Zhang
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
| | - Shixiao Kong
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
| | - Yunlei Zhou
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
| | - Xiaoliang Wang
- Key Laboratory of High Performance Polymer Materials and Technology of Ministry of Education, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China
| | - Dongchan Li
- College of Chemical Engineering and Technology, Engineering Research Center of Seawater Utilization Technology of Ministry of Education, State Key Laboratory of Reliability and Intelligence of Electrical Equipment , Hebei University of Technology , Tianjin 300130 , China
| | - Desheng Kong
- College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructure, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Key Laboratory of Artificial Functional Materials , Nanjing University , Nanjing 210093 , China
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58
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Branch B, Ionita A, Patterson BM, Schmalzer A, Clements B, Mueller A, Dattelbaum DM. A comparison of shockwave dynamics in stochastic and periodic porous polymer architectures. POLYMER 2019. [DOI: 10.1016/j.polymer.2018.10.074] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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59
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Auguste AD, Ward JW, Hardin JO, Kowalski BA, Guin TC, Berrigan JD, White TJ. Enabling and Localizing Omnidirectional Nonlinear Deformation in Liquid Crystalline Elastomers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1802438. [PMID: 30009428 DOI: 10.1002/adma.201802438] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/23/2018] [Indexed: 05/23/2023]
Abstract
Liquid crystalline elastomers (LCEs) are widely recognized for their exceptional promise as actuating materials. Here, the comparatively less celebrated but also compelling nonlinear response of these materials to mechanical load is examined. Prior examinations of planarly aligned LCEs exhibit unidirectional nonlinear deformation to mechanical loads. A methodology is presented to realize surface-templated homeotropic orientation in LCEs and omnidirectional nonlinearity in mechanical deformation. Inkjet printing of the homeotropic alignment surface localizes regions of homeotropic and planar orientation within a monolithic LCE element. The local control of the self-assembly and orientation of the LCE, when subject to rational design, yield functional materials continuous in composition with discontinuous mechanical deformation. The variation in mechanical deformation in the film can enable the realization of nontrivial performance. For example, a patterned LCE is prepared and shown to exhibit a near-zero Poisson's ratio. Further, it is demonstrated that the local control of deformation can enable the fabrication of rugged, flexible electronic devices. An additively manufactured device withstands complex mechanical deformations that would normally cause catastrophic failure.
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Affiliation(s)
- Anesia D Auguste
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH, 45433, USA
| | - Jeremy W Ward
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH, 45433, USA
| | - James O Hardin
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH, 45433, USA
- UES Inc., 401 Dayton Xenia Rd, Beavercreek, OH, 45432, USA
| | - Benjamin A Kowalski
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH, 45433, USA
- Azimuth Corporation, Beavercreek, OH, 45431, USA
| | - Tyler C Guin
- Azimuth Corporation, Beavercreek, OH, 45431, USA
| | - J Daniel Berrigan
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH, 45433, USA
| | - Timothy J White
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH, 45433, USA
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60
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Abstract
Architected 2D structures are of growing interest due to their unique mechanical and physical properties for applications in stretchable electronics, controllable phononic/photonic modulators, and switchable optical/electrical devices; however, the underpinning theory of understanding their elastic properties and enabling principles in search of emerging structures with well-defined arrangements and/or bonding connections of assembled elements has yet to be established. Here, we present two theoretical frameworks in mechanics-strain energy-based theory and displacement continuity-based theory-to predict the elastic properties of 2D structures and demonstrate their application in a search for novel architected 2D structures that are composed of heterogeneously arranged, arbitrarily shaped lattice cell structures with regulatory adjacent bonding connections of cells, referred to as heterogeneously architected 2D structures (HASs). By patterning lattice cell structures and tailoring their connections, the elastic properties of HASs can span a very broad range from nearly zero to beyond those of individual lattice cells by orders of magnitude. Interface indices that represent both the pattern arrangements of basic lattice cells and local bonding disconnections in HASs are also proposed and incorporated to intelligently design HASs with on-demand Young's modulus and geometric features. This study offers a theoretical foundation toward future architected structures by design with unprecedented properties and functions.
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61
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Fan D, Li M, Qiu J, Xing H, Jiang Z, Tang T. Novel Method for Preparing Auxetic Foam from Closed-Cell Polymer Foam Based on the Steam Penetration and Condensation Process. ACS APPLIED MATERIALS & INTERFACES 2018; 10:22669-22677. [PMID: 29847911 DOI: 10.1021/acsami.8b02332] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Auxetic materials are a class of materials possessing a negative Poisson's ratio. Here, we established a novel method for preparing auxetic foam from closed-cell polymer foam based on the steam penetration and condensation (SPC) process. Using polyethylene (PE) closed-cell foam as an example, the foams treated by the SPC process presented a negative Poisson's ratio during stretching and compression testing. The effect of steam-treated temperature and time on the conversion efficiency of negative-Poisson's ratio foam was investigated, and the mechanism of the SPC method for forming a reentrant structure was discussed. The results indicated that the presence of enough steam within the cells was a critical factor for the negative Poisson's ratio conversion in the SPC process. The pressure difference caused by steam condensation was the driving force for the conversion from conventional closed-cell foam to the negative-Poisson's ratio foam. Furthermore, the applicability of the SPC process for fabricating auxetic foam was studied by replacing PE foam by polyvinyl chloride foam with a closed-cell structure or replacing water steam by ethanol steam. The results verified the universality of the SPC process for fabricating auxetic foams from conventional foams with a closed-cell structure. In addition, we explored the potential application of the obtained auxetic foams by the SPC process in the fabrication of shape-memory polymer materials.
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Affiliation(s)
- Donglei Fan
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
- University of Science and Technology of China , Anhui 230026 , China
| | - Minggang Li
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
| | - Jian Qiu
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
| | - Haiping Xing
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
| | - Zhiwei Jiang
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
| | - Tao Tang
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
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62
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Chen D, Zheng X. Multi-material Additive Manufacturing of Metamaterials with Giant, Tailorable Negative Poisson's Ratios. Sci Rep 2018; 8:9139. [PMID: 29904093 PMCID: PMC6002359 DOI: 10.1038/s41598-018-26980-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 05/14/2018] [Indexed: 11/16/2022] Open
Abstract
Nature has evolved with a recurring strategy to achieve unusual mechanical properties through coupling variable elastic moduli from a few GPa to below KPa within a single tissue. The ability to produce multi-material, three-dimensional (3D) micro-architectures with high fidelity incorporating dissimilar components has been a major challenge in man-made materials. Here we show multi-modulus metamaterials whose architectural element is comprised of encoded elasticity ranging from rigid to soft. We found that, in contrast to ordinary architected materials whose negative Poisson’s ratio is dictated by their geometry, these type of metamaterials are capable of displaying Poisson’s ratios from extreme negative to zero, independent of their 3D micro-architecture. The resulting low density metamaterials is capable of achieving functionally graded, distributed strain amplification capabilities within the metamaterial with uniform micro-architectures. Simultaneous tuning of Poisson’s ratio and moduli within the 3D multi-materials could open up a broad array of material by design applications ranging from flexible armor, artificial muscles, to actuators and bio-mimetic materials.
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Affiliation(s)
- Da Chen
- Department of Mechanical Engineering, Virginia Tech, 635 Prices Fork Road, Blacksburg, VA, 24061, USA
| | - Xiaoyu Zheng
- Department of Mechanical Engineering, Virginia Tech, 635 Prices Fork Road, Blacksburg, VA, 24061, USA.
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63
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Kapnisi M, Mansfield C, Marijon C, Guex AG, Perbellini F, Bardi I, Humphrey EJ, Puetzer JL, Mawad D, Koutsogeorgis DC, Stuckey DJ, Terracciano CM, Harding SE, Stevens MM. Auxetic Cardiac Patches with Tunable Mechanical and Conductive Properties toward Treating Myocardial Infarction. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1800618. [PMID: 29875619 PMCID: PMC5985945 DOI: 10.1002/adfm.201800618] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Indexed: 05/27/2023]
Abstract
An auxetic conductive cardiac patch (AuxCP) for the treatment of myocardial infarction (MI) is introduced. The auxetic design gives the patch a negative Poisson's ratio, providing it with the ability to conform to the demanding mechanics of the heart. The conductivity allows the patch to interface with electroresponsive tissues such as the heart. Excimer laser microablation is used to micropattern a re-entrant honeycomb (bow-tie) design into a chitosan-polyaniline composite. It is shown that the bow-tie design can produce patches with a wide range in mechanical strength and anisotropy, which can be tuned to match native heart tissue. Further, the auxetic patches are conductive and cytocompatible with murine neonatal cardiomyocytes in vitro. Ex vivo studies demonstrate that the auxetic patches have no detrimental effect on the electrophysiology of both healthy and MI rat hearts and conform better to native heart movements than unpatterned patches of the same material. Finally, the AuxCP applied in a rat MI model results in no detrimental effect on cardiac function and negligible fibrotic response after two weeks in vivo. This approach represents a versatile and robust platform for cardiac biomaterial design and could therefore lead to a promising treatment for MI.
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Affiliation(s)
- Michaella Kapnisi
- Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ London, UK
| | - Catherine Mansfield
- National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Camille Marijon
- Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ London, UK; National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Anne Geraldine Guex
- Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ London, UK; National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Filippo Perbellini
- National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Ifigeneia Bardi
- National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Eleanor J Humphrey
- National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Jennifer L Puetzer
- Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ London, UK
| | - Damia Mawad
- Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ London, UK
| | | | - Daniel J Stuckey
- Centre for Advanced Biomedical Imaging, University College London, WC1E 6DD London, UK
| | | | - Sian E Harding
- National Heart and Lung Institute, Imperial College London, W12 0NN London, UK
| | - Molly M Stevens
- Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ London, UK
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64
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Moroni L, Burdick JA, Highley C, Lee SJ, Morimoto Y, Takeuchi S, Yoo JJ. Biofabrication strategies for 3D in vitro models and regenerative medicine. NATURE REVIEWS. MATERIALS 2018; 3:21-37. [PMID: 31223488 PMCID: PMC6586020 DOI: 10.1038/s41578-018-0006-y] [Citation(s) in RCA: 384] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Organs are complex systems composed of different cells, proteins and signalling molecules that are arranged in a highly ordered structure to orchestrate a myriad of functions in our body. Biofabrication strategies can be applied to engineer 3D tissue models in vitro by mimicking the structure and function of native tissue through the precise deposition and assembly of materials and cells. This approach allows the spatiotemporal control over cell-cell and cell-extracellular matrix communication and thus the recreation of tissue-like structures. In this Review, we examine biofabrication strategies for the construction of functional tissue replacements and organ models, focusing on the development of biomaterials, such as supramolecular and photosensitive materials, that can be processed using biofabrication techniques. We highlight bioprinted and bioassembled tissue models and survey biofabrication techniques for their potential to recreate complex tissue properties, such as shape, vasculature and specific functionalities. Finally, we discuss challenges, such as scalability and the foreign body response, and opportunities in the field and provide an outlook to the future of biofabrication in regenerative medicine.
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Affiliation(s)
- Lorenzo Moroni
- MERLN Institute for Technology-Inspired Regenerative Medicine, Department of Complex Tissue Regeneration, Maastricht University, Maastricht, Netherlands
| | - Jason A. Burdick
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Christopher Highley
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Sang Jin Lee
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Yuya Morimoto
- Institute of Industrial Science, University of Tokyo, Tokyo, Japan
| | - Shoji Takeuchi
- Institute of Industrial Science, University of Tokyo, Tokyo, Japan
| | - James J. Yoo
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
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65
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Hodaei A, Akhlaghi O, Khani N, Aytas T, Sezer D, Tatli B, Menceloglu YZ, Koc B, Akbulut O. Single Additive Enables 3D Printing of Highly Loaded Iron Oxide Suspensions. ACS APPLIED MATERIALS & INTERFACES 2018; 10:9873-9881. [PMID: 29474786 DOI: 10.1021/acsami.8b00551] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A single additive, a grafted copolymer, is designed to ensure the stability of suspensions of highly loaded iron oxide nanoparticles (IOPs) and to facilitate three-dimensional (3D) printing of these suspensions in the filament form. This poly (ethylene glycol)-grafted copolymer of N-[3(dimethylamino)propyl]methacrylamide and acrylic acid harnesses both electrostatic and steric repulsion to realize an optimum formulation for 3D printing. When used at 1.15 wt % (by the weight of IOPs), the suspension attains ∼81 wt % solid loading-96% of the theoretical limit as calculated by the Krieger-Dougherty equation. Rectangular, thick-walled toroidal, and thin-walled toroidal magnetic cores and a porous lattice structure are fabricated to demonstrate the utilization of this suspension as an ink for 3D printing. The electrical and magnetic properties of the magnetic cores are characterized through impedance spectroscopy (IS) and vibrating sample magnetometry (VSM), respectively. The IS indicates the possibility of utilizing wire-wound 3D printed cores as the inductive coils. The VSM verifies that the magnetic properties of IOPs before and after the ink formulation are kept almost unchanged because of the low dosage of the additive. This particle-targeted approach for the formulation of 3D printing inks allows embodiment of a fully aqueous system with utmost target material content.
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Affiliation(s)
- Amin Hodaei
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Omid Akhlaghi
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Navid Khani
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
- 3D Bioprinting Laboratory , Sabanci University Nanotechnology Research and Application Center , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Tunahan Aytas
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Dilek Sezer
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Buse Tatli
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Yusuf Z Menceloglu
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Bahattin Koc
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
- 3D Bioprinting Laboratory , Sabanci University Nanotechnology Research and Application Center , Orhanli-Tuzla , Istanbul 34956 , Turkey
| | - Ozge Akbulut
- Faculty of Engineering and Natural Sciences , Sabanci University , Orhanli-Tuzla , Istanbul 34956 , Turkey
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66
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Jiang Y, Li Y. 3D Printed Auxetic Mechanical Metamaterial with Chiral Cells and Re-entrant Cores. Sci Rep 2018; 8:2397. [PMID: 29402940 PMCID: PMC5799406 DOI: 10.1038/s41598-018-20795-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 01/24/2018] [Indexed: 11/09/2022] Open
Abstract
By combining the two basic deformation mechanisms for auxetic open-cell metamaterials, re-entrant angle and chirality, new hybrid chiral mechanical metamaterials are designed and fabricated via a multi-material 3D printer. Results from mechanical experiments on the 3D printed prototypes and systematic Finite Element (FE) simulations show that the new designs can achieve subsequential cell-opening mechanism under a very large range of overall strains (2.91%-52.6%). Also, the effective stiffness, the Poisson's ratio and the cell-opening rate of the new designs can be tuned in a wide range by tailoring the two independent geometric parameters: the cell size ratio [Formula: see text], and re-entrant angle θ. As an example application, a sequential particle release mechanism of the new designs was also systematically explored. This mechanism has potential application in drug delivery. The present new design concepts can be used to develop new multi-functional smart composites, sensors and/or actuators which are responsive to external load and/or environmental conditions.
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Affiliation(s)
- Yunyao Jiang
- Department of Mechanical Engineering, University of New Hampshire, Durham, NH03824, USA
| | - Yaning Li
- Department of Mechanical Engineering, University of New Hampshire, Durham, NH03824, USA.
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67
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Liu J, Zhang Y. Soft network materials with isotropic negative Poisson's ratios over large strains. SOFT MATTER 2018; 14:693-703. [PMID: 29226930 DOI: 10.1039/c7sm02052j] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Auxetic materials with negative Poisson's ratios have important applications across a broad range of engineering areas, such as biomedical devices, aerospace engineering and automotive engineering. A variety of design strategies have been developed to achieve artificial auxetic materials with controllable responses in the Poisson's ratio. The development of designs that can offer isotropic negative Poisson's ratios over large strains can open up new opportunities in emerging biomedical applications, which, however, remains a challenge. Here, we introduce deterministic routes to soft architected materials that can be tailored precisely to yield the values of Poisson's ratio in the range from -1 to 1, in an isotropic manner, with a tunable strain range from 0% to ∼90%. The designs rely on a network construction in a periodic lattice topology, which incorporates zigzag microstructures as building blocks to connect lattice nodes. Combined experimental and theoretical studies on broad classes of network topologies illustrate the wide-ranging utility of these concepts. Quantitative mechanics modeling under both infinitesimal and finite deformations allows the development of a rigorous design algorithm that determines the necessary network geometries to yield target Poisson ratios over desired strain ranges. Demonstrative examples in artificial skin with both the negative Poisson's ratio and the nonlinear stress-strain curve precisely matching those of the cat's skin and in unusual cylindrical structures with engineered Poisson effect and shape memory effect suggest potential applications of these network materials.
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Affiliation(s)
- Jianxing Liu
- Center for Mechanics and Materials, Center for Flexible Electronics Technology, AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
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68
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Ozbolat V, Dey M, Ayan B, Povilianskas A, Demirel MC, Ozbolat IT. 3D Printing of PDMS Improves Its Mechanical and Cell Adhesion Properties. ACS Biomater Sci Eng 2018; 4:682-693. [PMID: 33418756 DOI: 10.1021/acsbiomaterials.7b00646] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Despite extensive use of polydimethylsiloxane (PDMS) in medical applications, such as lab-on-a-chip or tissue/organ-on-a-chip devices, point-of-care devices, and biological machines, the manufacturing of PDMS devices is limited to soft-lithography and its derivatives, which prohibits the fabrication of geometrically complex shapes. With the recent advances in three-dimensional (3D) printing, use of PDMS for fabrication of such complex shapes has gained considerable interest. This research presents a detailed investigation on printability of PDMS elastomers over three concentrations for mechanical and cell adhesion studies. The results demonstrate that 3D printing of PDMS improved the mechanical properties of fabricated samples up to three fold compared to that of cast ones because of the decreased porosity of bubble entrapment. Most importantly, 3D printing facilitates the adhesion of breast cancer cells, whereas cast samples do not allow cellular adhesion without the use of additional coatings such as extracellular matrix proteins. Cells are able to adhere and grow in the grooves along the printed filaments demonstrating that 3D printed devices can be engineered with superior cell adhesion qualities compared to traditionally manufactured PDMS devices.
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Affiliation(s)
- Veli Ozbolat
- Mechanical Engineering Department, Ceyhan Engineering Faculty, Cukurova University, Adana 01950, Turkey
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69
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Chen D, Skouras M, Zhu B, Matusik W. Computational discovery of extremal microstructure families. SCIENCE ADVANCES 2018; 4:eaao7005. [PMID: 29376124 PMCID: PMC5777400 DOI: 10.1126/sciadv.aao7005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 12/19/2017] [Indexed: 05/12/2023]
Abstract
Modern fabrication techniques, such as additive manufacturing, can be used to create materials with complex custom internal structures. These engineered materials exhibit a much broader range of bulk properties than their base materials and are typically referred to as metamaterials or microstructures. Although metamaterials with extraordinary properties have many applications, designing them is very difficult and is generally done by hand. We propose a computational approach to discover families of microstructures with extremal macroscale properties automatically. Using efficient simulation and sampling techniques, we compute the space of mechanical properties covered by physically realizable microstructures. Our system then clusters microstructures with common topologies into families. Parameterized templates are eventually extracted from families to generate new microstructure designs. We demonstrate these capabilities on the computational design of mechanical metamaterials and present five auxetic microstructure families with extremal elastic material properties. Our study opens the way for the completely automated discovery of extremal microstructures across multiple domains of physics, including applications reliant on thermal, electrical, and magnetic properties.
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70
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Durban MM, Lenhardt JM, Wu AS, Small W, Bryson TM, Perez‐Perez L, Nguyen DT, Gammon S, Smay JE, Duoss EB, Lewicki JP, Wilson TS. Custom 3D Printable Silicones with Tunable Stiffness. Macromol Rapid Commun 2017; 39. [DOI: 10.1002/marc.201700563] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/04/2017] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Amanda S. Wu
- Lawrence Livermore National Laboratory Livermore CA 94550 USA
| | - Ward Small
- Lawrence Livermore National Laboratory Livermore CA 94550 USA
| | | | | | - Du T. Nguyen
- Lawrence Livermore National Laboratory Livermore CA 94550 USA
| | - Stuart Gammon
- Lawrence Livermore National Laboratory Livermore CA 94550 USA
| | - James E. Smay
- School of Chemical Engineering Oklahoma State University Stillwater OK 74078 USA
| | - Eric B. Duoss
- Lawrence Livermore National Laboratory Livermore CA 94550 USA
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71
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Liu Y, He K, Chen G, Leow WR, Chen X. Nature-Inspired Structural Materials for Flexible Electronic Devices. Chem Rev 2017; 117:12893-12941. [DOI: 10.1021/acs.chemrev.7b00291] [Citation(s) in RCA: 448] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yaqing Liu
- Innovative Centre for Flexible
Devices (iFLEX), School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Ke He
- Innovative Centre for Flexible
Devices (iFLEX), School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Geng Chen
- Innovative Centre for Flexible
Devices (iFLEX), School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Wan Ru Leow
- Innovative Centre for Flexible
Devices (iFLEX), School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Xiaodong Chen
- Innovative Centre for Flexible
Devices (iFLEX), School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
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72
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Yan P, Brown E, Su Q, Li J, Wang J, Xu C, Zhou C, Lin D. 3D Printing Hierarchical Silver Nanowire Aerogel with Highly Compressive Resilience and Tensile Elongation through Tunable Poisson's Ratio. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1701756. [PMID: 28834394 DOI: 10.1002/smll.201701756] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 06/17/2017] [Indexed: 06/07/2023]
Abstract
Metallic aerogels have attracted intense attention due to their superior properties, such as high electrical conductivity, ultralow densities, and large specific surface area. The preparation of metal aerogels with high efficiency and controllability remains challenge. A 3D freeze assembling printing technique integrated with drop-on-demand inkjet printing and freeze casting are proposed for metallic aerogels preparation. This technique enables tailoring both the macrostructure and microstructure of silver nanowire aerogels (SNWAs) by integrating programmable 3D printing and freeze casting, respectively. The density of the printed SNWAs is controllable, which can be down to 1.3 mg cm-3 . The ultralight SNWAs reach high electrical conductivity of 1.3 S cm-1 and exhibit excellent compressive resilience under 50% compressive strain. Remarkably, the printing methodology also enables tuning aerogel architectures with designed Poisson's ratio (from negative to positive). Moreover, these aerogel architechtures with tunable Poisson's ratio present highly electromechanical stability under high compressive and tensile strain (both strain up to 20% with fully recovery).
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Affiliation(s)
- Pengli Yan
- Department of Industrial and Manufacturing Systems Engineering, Kansas State University, Manhattan, KS, 66506, USA
| | - Emery Brown
- Department of Chemistry, Kansas State University, Manhattan, KS, 66506, USA
| | - Qing Su
- Nebraska Center for Energy Sciences Research, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Jun Li
- Department of Chemistry, Kansas State University, Manhattan, KS, 66506, USA
| | - Jian Wang
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Changxue Xu
- Department of Industrial, Manufacturing, and Systems Engineering, Texas Tech University, Lubbock, TX, 79409, USA
| | - Chi Zhou
- Department of Industrial and Systems Engineering, University at Buffalo, The State University of New York, Buffalo, NY, 14260, USA
| | - Dong Lin
- Department of Industrial and Manufacturing Systems Engineering, Kansas State University, Manhattan, KS, 66506, USA
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73
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The Isotropic and Cubic Material Designs. Recovery of the Underlying Microstructures Appearing in the Least Compliant Continuum Bodies. MATERIALS 2017; 10:ma10101137. [PMID: 28954406 PMCID: PMC5666943 DOI: 10.3390/ma10101137] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 09/20/2017] [Accepted: 09/21/2017] [Indexed: 11/17/2022]
Abstract
The paper discusses the problem of manufacturability of the minimum compliance designs of the structural elements made of two kinds of inhomogeneous materials: the isotropic and cubic. In both the cases the unit cost of the design is assumed as equal to the trace of the Hooke tensor. The Isotropic Material Design (IMD) delivers the optimal distribution of the bulk and shear moduli within the design domain. The Cubic Material Design (CMD) leads to the optimal material orientation and optimal distribution of the invariant moduli in the body made of the material of cubic symmetry. The present paper proves that the varying underlying microstructures (i.e., the representative volume elements (RVE) constructed of one or two isotropic materials) corresponding to the optimal designs constructed by IMD and CMD methods can be recovered by matching the values of the optimal moduli with the values of the effective moduli of the RVE computed by the theory of homogenization. The CMD method leads to a larger set of results, i.e., the set of pairs of optimal moduli. Moreover, special attention is focused on proper recovery of the microstructures in the auxetic sub-domains of the optimal designs.
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74
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Roh S, Parekh DP, Bharti B, Stoyanov SD, Velev OD. 3D Printing by Multiphase Silicone/Water Capillary Inks. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29. [PMID: 28590510 DOI: 10.1002/adma.201701554] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 04/17/2017] [Indexed: 05/09/2023]
Abstract
3D printing of polymers is accomplished easily with thermoplastics as the extruded hot melt solidifies rapidly during the printing process. Printing with liquid polymer precursors is more challenging due to their longer curing times. One curable liquid polymer of specific interest is polydimethylsiloxane (PDMS). This study demonstrates a new efficient technique for 3D printing with PDMS by using a capillary suspension ink containing PDMS in the form of both precured microbeads and uncured liquid precursor, dispersed in water as continuous medium. The PDMS microbeads are held together in thixotropic granular paste by capillary attraction induced by the liquid precursor. These capillary suspensions possess high storage moduli and yield stresses that are needed for direct ink writing. They could be 3D printed and cured both in air and under water. The resulting PDMS structures are remarkably elastic, flexible, and extensible. As the ink is made of porous, biocompatible silicone that can be printed directly inside aqueous medium, it can be used in 3D printed biomedical products, or in applications such as direct printing of bioscaffolds on live tissue. This study demonstrates a number of examples using the high softness, elasticity, and resilience of these 3D printed structures.
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Affiliation(s)
- Sangchul Roh
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695, USA
| | - Dishit P Parekh
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695, USA
| | - Bhuvnesh Bharti
- Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Simeon D Stoyanov
- Physical Chemistry and Soft Matter, Wageningen University, Wageningen, 6708, WE, The Netherlands
- Department of Mechanical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK
| | - Orlin D Velev
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695, USA
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75
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Warner JJ, Gillies AR, Hwang HH, Zhang H, Lieber RL, Chen S. 3D-printed biomaterials with regional auxetic properties. J Mech Behav Biomed Mater 2017; 76:145-152. [PMID: 28754244 DOI: 10.1016/j.jmbbm.2017.05.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/06/2017] [Indexed: 11/18/2022]
Abstract
Tissue engineering is replete with methods for inducing and mediating cell differentiation, which are crucial for ensuring proper regrowth of desired tissues. In this study, we developed a 3D-printed, non-positive Poisson's Ratio (NPPR) scaffold intended for future use in stretch-mediated cell differentiation applications, such as in muscle and tendon regeneration. We utilized dynamic optical projection stereolithography (DOPsL) to fabricate multi-layered, cell-laden NPPR scaffolds - these scaffolds can not only support aggregate cell growth, but can also be printed with locally-tunable force-displacement properties at length scales appropriate for tissue interaction. These NPPR multilayered mesh scaffolds can be embedded into highly elastic hydrogels in order to couple a reduced NPPR behavior to a normally Positive Poisson's Ratio (PPR) solid bulk material. This hybrid structure may potentially enable induced 'auxetic' behavior at the single-cell scale while tuning the Poisson's Ratio to a more isolated value. This would be uniquely suited for providing stretch-mediated effects for various cell-types within the tendon-to-muscle tissue transition.
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Affiliation(s)
- John J Warner
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Allison R Gillies
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Henry H Hwang
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Hong Zhang
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Richard L Lieber
- Department of Orthopaedic Surgery, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States; Rehabilitation Institute of Chicago, 345 East Superior St, Chicago, IL 60611, United States
| | - Shaochen Chen
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States.
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76
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Park HS, Kim SY. A perspective on auxetic nanomaterials. NANO CONVERGENCE 2017; 4:10. [PMID: 28473953 PMCID: PMC5392538 DOI: 10.1186/s40580-017-0104-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 04/07/2017] [Indexed: 06/07/2023]
Abstract
Nanomaterials have recently been found to exhibit auxetic behavior, or a negative Poisson's ratio, whereby the lateral dimensions of the material expand, rather than shrink, in response to applied tensile loading. In this brief review, we use the form of question-answer to highlight key points and outstanding issues related to the field of auxetic nanomaterials.
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Affiliation(s)
- Harold S. Park
- Department of Mechanical Engineering, Boston University, Boston, MA 02215 USA
| | - Sung Youb Kim
- Department of Mechanical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919 South Korea
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77
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Tanaka H, Suga K, Iwata N, Shibutani Y. Orthotropic Laminated Open-cell Frameworks Retaining Strong Auxeticity under Large Uniaxial Loading. Sci Rep 2017; 7:39816. [PMID: 28051133 PMCID: PMC5209672 DOI: 10.1038/srep39816] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 11/28/2016] [Indexed: 11/10/2022] Open
Abstract
Anisotropic materials form inside living tissue and are widely applied in engineered structures, where sophisticated structural and functional design principles are essential to employing these materials. This paper presents a candidate laminated open-cell framework, which is an anisotropic material that shows remarkable mechanical performance. Using additive manufacturing, artificial frameworks are fabricated by lamination of in-plane orthotropic microstructures made of elbowed beam and column members; this fabricated structure features orthogonal anisotropy in three-dimensional space. Uniaxial loading tests reveal strong auxeticity (high negative Poisson's ratios) in the out-of-plane direction, which is retained reproducibly up to the nonlinear elastic region, and is equal under tensile and compressive loading. Finite element simulations support the observed auxetic behaviors for a unit cell in the periodic framework, which preserve the theoretical elastic properties of an orthogonal solid. These findings open the possibility of conceptual materials design based on geometry.
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Affiliation(s)
- Hiro Tanaka
- Department of Mechanical Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Kaito Suga
- Department of Mechanical Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Naoki Iwata
- Department of Mechanical Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yoji Shibutani
- Department of Mechanical Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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78
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Truby RL, Lewis JA. Printing soft matter in three dimensions. Nature 2016; 540:371-378. [DOI: 10.1038/nature21003] [Citation(s) in RCA: 866] [Impact Index Per Article: 108.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/15/2016] [Indexed: 12/11/2022]
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79
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Huang C, Chen L. Negative Poisson's Ratio in Modern Functional Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:8079-8096. [PMID: 27378610 DOI: 10.1002/adma.201601363] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 04/20/2016] [Indexed: 05/28/2023]
Abstract
Materials with negative Poisson's ratio attract considerable attention due to their underlying intriguing physical properties and numerous promising applications, particularly in stringent environments such as aerospace and defense areas, because of their unconventional mechanical enhancements. Recent progress in materials with a negative Poisson's ratio are reviewed here, with the current state of research regarding both theory and experiment. The inter-relationship between the underlying structure and a negative Poisson's ratio is discussed in functional materials, including macroscopic bulk, low-dimensional nanoscale particles, films, sheets, or tubes. The coexistence and correlations with other negative indexes (such as negative compressibility and negative thermal expansion) are also addressed. Finally, open questions and future research opportunities are proposed for functional materials with negative Poisson's ratios.
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Affiliation(s)
- Chuanwei Huang
- Shenzhen Key Laboratory of Special Functional Materials, College of Materials Science and Engineering, Shenzhen University, Nanshan District, Shenzhen, 518060, Guangdong, China.
| | - Lang Chen
- Department of Physics, South University of Science and Technology, Nanshan District, Shenzhen, 518055, Guangdong, China.
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80
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Jason NN, Wang SJ, Bhanushali S, Cheng W. Skin inspired fractal strain sensors using a copper nanowire and graphite microflake hybrid conductive network. NANOSCALE 2016; 8:16596-16605. [PMID: 27714094 DOI: 10.1039/c6nr04056j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This work demonstrates a facile "paint-on" approach to fabricate highly stretchable and highly sensitive strain sensors by combining one-dimensional copper nanowire networks with two-dimensional graphite microflakes. This paint-on approach allows for the fabrication of electronic skin (e-skin) patches which can directly replicate with high fidelity the human skin surface they are on, regardless of the topological complexity. This leads to high accuracy for detecting biometric signals for applications in personalised wearable sensors. The copper nanowires contribute to high stretchability and the graphite flakes offer high sensitivity, and their hybrid coating offers the advantages of both. To understand the topological effects on the sensing performance, we utilized fractal shaped elastomeric substrates and systematically compared their stretchability and sensitivity. We could achieve a high stretchability of up to 600% and a maximum gauge factor of 3000. Our simple yet efficient paint-on approach enabled facile fine-tuning of sensitivity/stretchability simply by adjusting ratios of 1D vs. 2D materials in the hybrid coating, and the topological structural designs. This capability leads to a wide range of biomedical sensors demonstrated here, including pulse sensors, prosthetic hands, and a wireless ankle motion sensor.
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Affiliation(s)
- Naveen N Jason
- Department of Chemical Engineering, Faculty of Engineering, Monash University, Clayton 3800, Victoria, Australia.
| | - Stephen J Wang
- International Tangible Interaction Design Lab (ITIDLab), Monash University, Clayton, Victoria 3800, Australia and Interaction Design, Department of Design, Faculty of Art Design and Architecture, 900 Dandenong Road, Caulfield East 3145, Victoria, Australia
| | - Sushrut Bhanushali
- Department of Chemical Engineering, Faculty of Engineering, Monash University, Clayton 3800, Victoria, Australia. and IITB Monash Research Academy, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Wenlong Cheng
- Department of Chemical Engineering, Faculty of Engineering, Monash University, Clayton 3800, Victoria, Australia.
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81
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Jiang JW, Chang T, Guo X. Tunable negative Poisson's ratio in hydrogenated graphene. NANOSCALE 2016; 8:15948-15953. [PMID: 27536878 DOI: 10.1039/c6nr04976a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We perform molecular dynamics simulations to investigate the effect of hydrogenation on the Poisson's ratio of graphene. It is found that the value of the Poisson's ratio of graphene can be effectively tuned from positive to negative by varying the percentage of hydrogenation. Specifically, the Poisson's ratio decreases with an increase in the percentage of hydrogenation, and reaches a minimum value of -0.04 when the percentage of hydrogenation is about 50%. The Poisson's ratio starts to increase upon a further increase of the percentage of hydrogenation. The appearance of a minimum negative Poisson's ratio in the hydrogenated graphene is attributed to the suppression of the hydrogenation-induced ripples during the stretching of graphene. Our results demonstrate that hydrogenation is a valuable approach for tuning the Poisson's ratio from positive to negative in graphene.
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Affiliation(s)
- Jin-Wu Jiang
- Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University, Shanghai 200072, People's Republic of China.
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82
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Lin Z, Pick A, Lončar M, Rodriguez AW. Enhanced Spontaneous Emission at Third-Order Dirac Exceptional Points in Inverse-Designed Photonic Crystals. PHYSICAL REVIEW LETTERS 2016; 117:107402. [PMID: 27636493 DOI: 10.1103/physrevlett.117.107402] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Indexed: 06/06/2023]
Abstract
We formulate and exploit a computational inverse-design method based on topology optimization to demonstrate photonic crystal structures supporting complex spectral degeneracies. In particular, we discover photonic crystals exhibiting third-order Dirac points formed by the accidental degeneracy of monopolar, dipolar, and quadrupolar modes. We show that, under suitable conditions, these modes can coalesce and form a third-order exceptional point, leading to strong modifications in the spontaneous emission (SE) of emitters, related to the local density of states. We find that SE can be enhanced by a factor of 8 in passive structures, with larger enhancements ∼sqrt[n^{3}] possible at exceptional points of higher order n.
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Affiliation(s)
- Zin Lin
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Adi Pick
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Marko Lončar
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Alejandro W Rodriguez
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
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83
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Jiang JW, Chang T, Guo X, Park HS. Intrinsic Negative Poisson's Ratio for Single-Layer Graphene. NANO LETTERS 2016; 16:5286-90. [PMID: 27408994 DOI: 10.1021/acs.nanolett.6b02538] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Negative Poisson's ratio (NPR) materials have drawn significant interest because the enhanced toughness, shear resistance, and vibration absorption that typically are seen in auxetic materials may enable a range of novel applications. In this work, we report that single-layer graphene exhibits an intrinsic NPR, which is robust and independent of its size and temperature. The NPR arises due to the interplay between two intrinsic deformation pathways (one with positive Poisson's ratio, the other with NPR), which correspond to the bond stretching and angle bending interactions in graphene. We propose an energy-based deformation pathway criteria, which predicts that the pathway with NPR has lower energy and thus becomes the dominant deformation mode when graphene is stretched by a strain above 6%, resulting in the NPR phenomenon.
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Affiliation(s)
- Jin-Wu Jiang
- Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University , Shanghai 200072, People's Republic of China
| | - Tienchong Chang
- Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University , Shanghai 200072, People's Republic of China
| | - Xingming Guo
- Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University , Shanghai 200072, People's Republic of China
| | - Harold S Park
- Department of Mechanical Engineering, Boston University , Boston, Massachusetts 02215, United States
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84
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Wu L, Li B, Zhou J. Isotropic Negative Thermal Expansion Metamaterials. ACS APPLIED MATERIALS & INTERFACES 2016; 8:17721-17727. [PMID: 27333052 DOI: 10.1021/acsami.6b05717] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Negative thermal expansion materials are important and desirable in science and engineering applications. However, natural materials with isotropic negative thermal expansion are rare and usually unsatisfied in performance. Here, we propose a novel method to achieve two- and three-dimensional negative thermal expansion metamaterials via antichiral structures. The two-dimensional metamaterial is constructed with unit cells that combine bimaterial strips and antichiral structures, while the three-dimensional metamaterial is fabricated by a multimaterial 3D printing process. Both experimental and simulation results display isotropic negative thermal expansion property of the samples. The effective coefficient of negative thermal expansion of the proposed models is demonstrated to be dependent on the difference between the thermal expansion coefficient of the component materials, as well as on the circular node radius and the ligament length in the antichiral structures. The measured value of the linear negative thermal expansion coefficient of the three-dimensional sample is among the largest achieved in experiments to date. Our findings provide an easy and practical approach to obtaining materials with tunable negative thermal expansion on any scale.
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Affiliation(s)
- Lingling Wu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University , Beijing 100084, China
| | - Bo Li
- Advanced Materials Institute, Shenzhen Graduate School, Tsinghua University , Shenzhen, 518055, China
| | - Ji Zhou
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University , Beijing 100084, China
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85
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Abstract
The ability to three-dimensionally interweave biological and functional materials could enable the creation of bionic devices possessing unique and compelling geometries, properties, and functionalities. Indeed, interfacing high performance active devices with biology could impact a variety of fields, including regenerative bioelectronic medicines, smart prosthetics, medical robotics, and human-machine interfaces. Biology, from the molecular scale of DNA and proteins, to the macroscopic scale of tissues and organs, is three-dimensional, often soft and stretchable, and temperature sensitive. This renders most biological platforms incompatible with the fabrication and materials processing methods that have been developed and optimized for functional electronics, which are typically planar, rigid and brittle. A number of strategies have been developed to overcome these dichotomies. One particularly novel approach is the use of extrusion-based multi-material 3D printing, which is an additive manufacturing technology that offers a freeform fabrication strategy. This approach addresses the dichotomies presented above by (1) using 3D printing and imaging for customized, hierarchical, and interwoven device architectures; (2) employing nanotechnology as an enabling route for introducing high performance materials, with the potential for exhibiting properties not found in the bulk; and (3) 3D printing a range of soft and nanoscale materials to enable the integration of a diverse palette of high quality functional nanomaterials with biology. Further, 3D printing is a multi-scale platform, allowing for the incorporation of functional nanoscale inks, the printing of microscale features, and ultimately the creation of macroscale devices. This blending of 3D printing, novel nanomaterial properties, and 'living' platforms may enable next-generation bionic systems. In this review, we highlight this synergistic integration of the unique properties of nanomaterials with the versatility of extrusion-based 3D printing technologies to interweave nanomaterials and fabricate novel bionic devices.
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Affiliation(s)
- Yong Lin Kong
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Maneesh K. Gupta
- Air Force Research Laboratories, Wright-Patterson Air Force Base, Ohio 45433, USA
| | - Blake N. Johnson
- Department of Industrial and Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Michael C. McAlpine
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
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86
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Li Y, Zeng C. Room-Temperature, Near-Instantaneous Fabrication of Auxetic Materials with Constant Poisson's Ratio over Large Deformation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:2822-2826. [PMID: 26861805 DOI: 10.1002/adma.201505650] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/05/2016] [Indexed: 06/05/2023]
Abstract
A novel compressed carbon dioxide assisted fabrication method is demonstrated to produce auxetic PU foam. Auxetic PU foams can be fabricated at room temperature (25°C) in several seconds with compressed CO2. This technology overcomes some key challenging issues in the large-scale production of auxetic PU foams.
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Affiliation(s)
- Yan Li
- High-Performance Materials Institute, Florida State University, Tallahassee, FL, 32310, USA
- Department of Industrial and Manufacturing Engineering, FAMU-FSU College of Engineering, Tallahassee, FL, 32310, USA
| | - Changchun Zeng
- High-Performance Materials Institute, Florida State University, Tallahassee, FL, 32310, USA
- Department of Industrial and Manufacturing Engineering, FAMU-FSU College of Engineering, Tallahassee, FL, 32310, USA
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