1
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Zhu Y, Cao X, Yang S, Hu J, Li B, Chen Z. Negative Poisson's ratio of sulfides dominated by strong intralayer electron repulsion. Phys Chem Chem Phys 2024; 26:20852-20863. [PMID: 39044551 DOI: 10.1039/d4cp02174f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Geometrical variations in a particular structure or other mechanical factors are often cited as the cause of a negative Poisson's ratio (NPR). These factors are independent of the electronic properties of the materials. This work investigates a class of two-dimensional (2D) sulfides with the chemical formula MX2 (M = Ti, Cr, Mn, Fe, Co, X = S) using first-principles calculations. Among them, monolayered TiS2, CrS2, and MnS2 were found to exhibit a structure-independent NPR. The strong strain response of intra-layer interactions is responsible for this unique phenomenon. This can be traced to the lone pair of electrons of the S atoms and the weak electronegativity of the central atoms in multi-orbital hybridization. Our study provides valuable insights and useful guidelines for designing innovative NPR materials.
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Affiliation(s)
- Yucheng Zhu
- School of Chemical Engineering, Northwest University, Xi'an, 710069, P. R. China.
| | - Xiaofei Cao
- School of Chemical Engineering, Northwest University, Xi'an, 710069, P. R. China.
| | - Shuaijun Yang
- School of Chemical Engineering, Northwest University, Xi'an, 710069, P. R. China.
| | - Jun Hu
- School of Chemical Engineering, Northwest University, Xi'an, 710069, P. R. China.
| | - Baotong Li
- Key Laboratory of Education Ministry for Modern Design & Rotor-Bearing System, Xi'an Jiaotong University, Xi'an, 710049, P. R. China.
| | - Zhong Chen
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore.
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2
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Li Z, Li Y, Li Y. Effects of Three Different Kinds of Foaming Medium on the Properties of Expanded Thermal Plastic Polyurethane Prepared via Supercritical Carbon Dioxide Foaming. Polymers (Basel) 2024; 16:2224. [PMID: 39125250 PMCID: PMC11314948 DOI: 10.3390/polym16152224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 07/23/2024] [Accepted: 07/26/2024] [Indexed: 08/12/2024] Open
Abstract
Hot air, water, and glycerol were studied as foaming mediums for the production of ETPU to evaluate their influence on the behavior of the foam and compare the optimal particles for each of the foaming temperatures selected. The results showed that the times of water foaming and glycerol foaming were shorter by about 2/3 than with hot-air foaming. The best foaming temperatures for hot-air foaming, glycerol foaming, and water foaming are 110-115 °C, 75 °C, and 90 °C, respectively. The particles of glycerol foam have a matte appearance and their gloss is not very good. However, the particles in hot-air foaming are light, and the gloss is very satisfactory. The gloss of the surface of water-foaming particles is dim. At the same time, there is a faint matte appearance. Particles made with glycerol foaming and water foaming are more even than those made with hot-air foaming. The density of foaming materials from glycerol foaming, hot-air foaming, and water foaming are raised accordingly, while the hardness of foaming materials from glycerol foaming, water foaming, and hot-air foaming are successively increased.
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Affiliation(s)
- Zhou Li
- College of Intelligent Systens Science and Engineering, Hubei Minzu University, Enshi 445000, China; (Z.L.); (Y.L.)
| | - Yuanyuan Li
- College of Intelligent Systens Science and Engineering, Hubei Minzu University, Enshi 445000, China; (Z.L.); (Y.L.)
| | - Yingru Li
- College of Intelligent Systens Science and Engineering, Hubei Minzu University, Enshi 445000, China; (Z.L.); (Y.L.)
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China
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3
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Huang M, Zhang C, Hou F, Yang H, Ding N. Stabilization and strengthening effects of filamentous nanocellulose in the foam forming of quartz paper. Int J Biol Macromol 2024; 263:130251. [PMID: 38368991 DOI: 10.1016/j.ijbiomac.2024.130251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 01/31/2024] [Accepted: 02/15/2024] [Indexed: 02/20/2024]
Abstract
Compared with traditional papermaking, foam forming is a new papermaking technology that uses foam instead of water to disperse fibres, which can effectively solve the problem of poor evenness of ceramic paper, but the instability of foam itself affects the application of foam forming technology. Herein, a highly stable foaming agent for foam forming technology was prepared via physical reaction of lauryl dimethyl amine oxide (OB-2) with filamentous nanocellulose (cellulose nanofiber (CNF-C) and bacterial cellulose (BC)). Then, the quartz paper was prepared by foam forming technology. Firstly, hydrogen bond interactions between hydroxyl groups of the filamentous nanocellulose and hydrophilic moieties on OB-2 enabled the formation of a 3D nanonetwork layer on the surface of the bubble, which extended the half-life of the bubble and effectively prevented the bubble from bursting or coalescing. Then, the foam was extruded and cracked, and the filamentous nanocellulose was retained on the quartz fibres to prepare filamentous nanocellulose/quartz fibre paper by foam forming technology. The quartz paper exhibited excellent evenness and mechanical properties. In conclusion, the research of foam forming technology is of great significance to the application and development of special paper.
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Affiliation(s)
- Mengle Huang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Chunhui Zhang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Fuqing Hou
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Huikang Yang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Nengxin Ding
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
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4
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Dong S, Hu H. Sensors Based on Auxetic Materials and Structures: A Review. MATERIALS (BASEL, SWITZERLAND) 2023; 16:ma16093603. [PMID: 37176486 PMCID: PMC10179841 DOI: 10.3390/ma16093603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/01/2023] [Accepted: 05/06/2023] [Indexed: 05/15/2023]
Abstract
Auxetic materials exhibit a negative Poisson's ratio under tension or compression, and such counter-intuitive behavior leads to enhanced mechanical properties such as shear resistance, impact resistance, and shape adaptability. Auxetic materials with these excellent properties show great potential applications in personal protection, medical health, sensing equipment, and other fields. However, there are still many limitations in them, from laboratory research to real applications. There have been many reported studies applying auxetic materials or structures to the development of sensing devices in anticipation of improving sensitivity. This review mainly focuses on the use of auxetic materials or auxetic structures in sensors, providing a broad review of auxetic-based sensing devices. The material selection, structure design, preparation method, sensing mechanism, and sensing performance are introduced. In addition, we explore the relationship between the auxetic mechanism and the sensing performance and summarize how the auxetic behavior enhances the sensitivity. Furthermore, potential applications of sensors based on the auxetic mechanism are discussed, and the remaining challenges and future research directions are suggested. This review may help to promote further research and application of auxetic sensing devices.
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Affiliation(s)
- Shanshan Dong
- School of Fashion and Textiles, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong 999077, China
| | - Hong Hu
- School of Fashion and Textiles, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong 999077, China
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5
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Li X, Liu QB, Tang Y, Li W, Ding N, Liu Z, Fu HH, Dong S, Li X, Yang J. Quintuple Function Integration in Two-Dimensional Cr(II) Five-Membered Heterocyclic Metal Organic Frameworks via Tuning Ligand Spin and Lattice Symmetry. J Am Chem Soc 2023; 145:7869-7878. [PMID: 36926870 DOI: 10.1021/jacs.2c12780] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Two-dimensional (2D) semiconductors (SCs) integrated with two or more functions are the cornerstone for constructing multifunctional nanodevices but remain largely limited. Here, by tuning the spin state of organic linkers and the symmetry/topology of crystal lattices, we predict a class of unprecedented multifunctional SCs in 2D Cr(II) five-membered heterocyclic metal organic frameworks that simultaneously possess auxetic effect, room-temperature ferrimagnetism, chiral ferroelectricity (FE), electrically reversible spin polarization, and topological nodal lines/points. Taking 2D Cr(TDZ)2 (TDZ = 1.2.5-thiadiazole) as an exemplification, the auxetic effect is produced by the antitetra-chiral lattice structure. The high temperature ferrimagnetism originates from the strong d-p direct magnetic exchange interaction between Cr cations and TDZ doublet radical anions. Meanwhile, the clockwise-counterclockwise alignment of TDZ's dipoles results in unique 2D chiral FE with atomic-scale vortex-antivortex states. 2D Cr(TDZ)2 is an intrinsic bipolar magnetic SC where half-metallic conduction with switchable spin-polarization direction can be induced by applying a gate voltage. In addition, the symmetry of the little group C4 of the lattice structure endows 2D Cr(TDZ)2 with topological nodal lines and a quadratic nodal point in the Brillouin zone near the Fermi level.
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Affiliation(s)
- Xiangyang Li
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.,School of Materials Science and Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Qing-Bo Liu
- Hubei Key Laboratory of Optical Information and Pattern Recognition, Wuhan Institute of Technology, Wuhan 430073, China.,School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yongsen Tang
- School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Wei Li
- Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Ning Ding
- School of Physics, Southeast University, Nanjing 211189, China
| | - Zhao Liu
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hua-Hua Fu
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Shuai Dong
- School of Physics, Southeast University, Nanjing 211189, China
| | - Xingxing Li
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.,Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China.,Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jinlong Yang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.,Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China.,Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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6
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Chen XY, Hamdi O, Rodrigue D. Conversion of low density polyethylene foams into auxetic metamaterials. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Xiao Yuan Chen
- Department of Chemical Engineering Université Laval Quebec Qubec Canada
| | - Ouassim Hamdi
- Department of Chemical Engineering Université Laval Quebec Qubec Canada
| | - Denis Rodrigue
- Department of Chemical Engineering Université Laval Quebec Qubec Canada
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7
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Crosslinked Polyethylene (XLPE), Recycling via Foams. Polymers (Basel) 2022; 14:polym14132589. [PMID: 35808636 PMCID: PMC9268835 DOI: 10.3390/polym14132589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/12/2022] [Accepted: 06/23/2022] [Indexed: 12/10/2022] Open
Abstract
Efficient recycling of crosslinked polyethylene has been challenging due to manufacturing difficulties caused by chemical crosslinking. This study focuses on simple processing via solid waste powder generation and particle fining for the subsequent crosslinked polyethylene inclusion and dispersion in rigid polyurethane foam. In addition, the concentration effects of crosslinked polyethylene in polyurethane were studied, showing a well-controlled foam microstructure with uniform pores, retained strength, better thermal degradation resistance, and, more importantly, increased thermal capabilities. Thus, the simple mechanical processing of crosslinked polyethylene and chemical urethane foaming showed the massive potential of recycling large amounts of crosslinked polyethylene in foams for broad applications in food packaging, house insulation, and sound reduction.
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8
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Veerabagu U, Palza H, Quero F. Review: Auxetic Polymer-Based Mechanical Metamaterials for Biomedical Applications. ACS Biomater Sci Eng 2022; 8:2798-2824. [PMID: 35709523 DOI: 10.1021/acsbiomaterials.2c00109] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Over the last three decades but more particularly during the last 5 years, auxetic mechanical metamaterials constructed from precisely architected polymer-based materials have attracted considerable attention due to their fascinating mechanical properties. These materials present a negative Poisson's ratio and therefore unusual mechanical behavior, which has resulted in enhanced static modulus, energy adsorption, and shear resistance, as compared with the bulk properties of polymers. Novel advanced polymer processing and fabrication techniques, and in particular additive manufacturing, allow one to design complex and customizable polymer architectures that are particularly relevant to fabricate auxetic mechanical metamaterials. Although these metamaterials exhibit exotic mechanical properties with potential applications in several engineering fields, biomedical applications seem to be one of the most relevant with a growing number of articles published over recent years. As a result, special focus is needed to understand the potential of these structures and foster theoretical and experimental investigations on the potential benefits of the unusual mechanical properties of these materials on the way to high performance biomedical applications. The present Review provides up to date information on the recent progress of polymer-based auxetic mechanical metamaterials mainly fabricated using additive manufacturing methods with a special focus toward biomedical applications including tissue engineering as well as medical devices including stents and sensors.
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Affiliation(s)
- Udayakumar Veerabagu
- Laboratorio de Nanocelulosa y Biomateriales, Departamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Beauchef 851, Santiago 8370456, Chile
| | - Humberto Palza
- Laboratorio de Ingeniería de Polímeros, Departamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Beauchef 851, Santiago 8370456, Chile.,IMPACT, Center of Interventional Medicine for Precision and Advanced Cellular Therapy, Avenida Beauchef 851, Santiago 8370456, Chile.,Millennium Nucleus on Smart Soft Mechanical Metamaterials, Avenida Beauchef 851, Santiago 8370456, Chile
| | - Franck Quero
- Laboratorio de Nanocelulosa y Biomateriales, Departamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Beauchef 851, Santiago 8370456, Chile.,Millennium Nucleus on Smart Soft Mechanical Metamaterials, Avenida Beauchef 851, Santiago 8370456, Chile
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9
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Nazari Z, Ahmadi H, Liaghat G, Vahid S. Investigation on the compressive properties of auxetic foams under different loading rates. POLYM ENG SCI 2022. [DOI: 10.1002/pen.25959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Zahra Nazari
- Department of Mechanical Engineering Tarbiat Modares University Tehran Iran
| | - Hamed Ahmadi
- Department of Mechanical Engineering Tarbiat Modares University Tehran Iran
| | - Gholamhossein Liaghat
- Department of Mechanical Engineering Tarbiat Modares University Tehran Iran
- Department of Mechanical Engineering Kingston University London UK
| | - Samireh Vahid
- Department of Aerospace and Aircraft Engineering Kingston University London UK
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10
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Abstract
Auxetic foams have previously been shown to have benefits including higher indentation resistance than their conventional counterparts, due to their negative Poisson’s ratio, making them better at resisting penetration by concentrated loads. The Poisson’s ratio and Young’s modulus of auxetic open cell foams have rarely been measured at the high compressive strain rates typical during impacts of energy absorbing material in sporting protective equipment. Auxetic closed cell foams are less common than their open cell counterparts, and only their quasi-static characteristics have been previously reported. It is, therefore, unclear how the Poisson’s ratio of auxetic foam, and associated benefits such as increased indentation resistance shown at low strain rates, would transfer to the high strain rates expected under impact. The aim of this study was to measure the effect of strain rate on the stiffness and Poisson’s ratio of auxetic and conventional foam. Auxetic open cell and closed cell polymer foams were fabricated, then compression tested to ~80% strain at applied rates up to 200 s−1, with Poisson’s ratios obtained from optical full-field strain mapping. Open cell foam quasi-static Poisson’s ratios ranged from −2.0 to 0.4, with a narrower range of −0.1 to 0.3 for closed cell foam. Poisson’s ratios of auxetic foams approximately halved in magnitude between the minimum and maximum strain rates. Open cell foam quasi-static Young’s moduli were between 0.02 and 0.09 MPa, whereas closed cell foams Young’s moduli were ~1 MPa, which is like foam in protective equipment. The Young’s moduli of the auxetic foams approximately doubled at the highest applied strain rate of 200 s−1.
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Fan D, Shi Z, Li N, Qiu J, Xing H, Jiang Z, Li M, Tang T. Novel Method for Preparing a High-Performance Auxetic Foam Directly from Polymer Resin by a One-Pot CO 2 Foaming Process. ACS APPLIED MATERIALS & INTERFACES 2020; 12:48040-48048. [PMID: 33044821 DOI: 10.1021/acsami.0c15383] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
So far, negative Poisson's ratio foam (auxetic foam) is usually prepared by the transformation of conventional polymer foam, and it is a challenge to prepare auxetic foam directly from polymer resin. In this work, a novel method based on the synergism between the phase transition of water and the permeability rate difference of the CO2 blowing agent from air in the foaming process is put forward to prepare auxetic foam directly from the polymer resin. Using this method, herein, nylon elastomer (NE) foam with auxetic behavior is successfully prepared from NE resin by a one-pot CO2 foaming method inside an autoclave aided by water; the obtained auxetic foam has a Poisson's ratio value of -1.29 and has excellent tensile cycle stability and energy absorption performance. This method breaks through the bottleneck for preparing auxetic foams from the polymer resin directly, which is also green and environment-friendly. It is believed that the abovementioned method also applies to other thermoplastic polymers, which paves a way for designing and preparing multifunctional auxetic foam materials in the future via a one-pot CO2 foaming process. Furthermore, this work first demonstrates that the transformation between auxetic foam and positive Poisson's ratio foam is reversible due to the closed cell structure, which provides an opportunity to reversibly adjust the performance and the shape of polymer foam 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, Hefei 230026, China
| | - Zhiyuan Shi
- 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, Hefei 230026, China
| | - Niexin 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
| | - Minggang Li
- 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
- University of Science and Technology of China, Hefei 230026, China
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12
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Striking effect of carbon nanotubes on adjusting sc-CO2 foaming performance of PS/LLDPE blends and forming semi-open cellular structure. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122896] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Suethao S, Shah DU, Smitthipong W. Recent Progress in Processing Functionally Graded Polymer Foams. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E4060. [PMID: 32933128 PMCID: PMC7560401 DOI: 10.3390/ma13184060] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/05/2020] [Accepted: 09/08/2020] [Indexed: 01/08/2023]
Abstract
Polymer foams are an important class of engineering material that are finding diverse applications, including as structural parts in automotive industry, insulation in construction, core materials for sandwich composites, and cushioning in mattresses. The vast majority of these manufactured foams are homogeneous with respect to porosity and structural properties. In contrast, while cellular materials are also ubiquitous in nature, nature mostly fabricates heterogeneous foams, e.g., cellulosic plant stems like bamboo, or a human femur bone. Foams with such engineered porosity distribution (graded density structure) have useful property gradients and are referred to as functionally graded foams. Functionally graded polymer foams are one of the key emerging innovations in polymer foam technology. They allow enhancement in properties such as energy absorption, more efficient use of material, and better design for specific applications, such as helmets and tissue restorative scaffolds. Here, following an overview of key processing parameters for polymer foams, we explore recent developments in processing functionally graded polymer foams and their emerging structures and properties. Processes can be as simple as utilizing different surface materials from which the foam forms, to as complex as using microfluidics. We also highlight principal challenges that need addressing in future research, the key one being development of viable generic processes that allow (complete) control and tailoring of porosity distribution on an application-by-application basis.
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Affiliation(s)
- Supitta Suethao
- Specialized Center of Rubber and Polymer Materials in Agriculture and Industry (RPM), Department of Materials Science, Faculty of Science, Kasetsart University, Chatuchak, Bangkok 10900, Thailand;
| | - Darshil U. Shah
- Centre for Natural Material Innovation, Department of Architecture, University of Cambridge, Cambridge CB2 1PX, UK;
| | - Wirasak Smitthipong
- Specialized Center of Rubber and Polymer Materials in Agriculture and Industry (RPM), Department of Materials Science, Faculty of Science, Kasetsart University, Chatuchak, Bangkok 10900, Thailand;
- Office of Natural Rubber Research Program, Thailand Science Research and Innovation (TSRI), Chatuchak, Bangkok 10900, Thailand
- Office of Research Integration on Target–Based Natural Rubber, National Research Council of Thailand (NRCT), Chatuchak, Bangkok 10900, Thailand
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14
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Zhang F, Xia Y, Liu Y, Leng J. Nano/microstructures of shape memory polymers: from materials to applications. NANOSCALE HORIZONS 2020; 5:1155-1173. [PMID: 32567643 DOI: 10.1039/d0nh00246a] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Shape memory polymers (SMPs) are macromolecules in which linear chains and crosslinking points play a key role in providing a shape memory effect. As smart polymers, SMPs have the ability to change shape, stiffness, size, and structure when exposed to external stimuli, leading to potential uses for SMPs throughout our daily lives in a diverse range of areas including the aerospace and automotive industries, robotics, biomedical engineering, smart textiles, and tactile devices. SMPs can be fabricated in many forms and sizes from the nanoscale to the macroscale, including nanofibers, nanoparticles, thin films, microfoams, and bulk devices. The introduction of nanostructure into SMPs can result in enhanced mechanical properties, unique structural color, specific surface area, and multiple functions. It is necessary to enhance the current understanding of the various nano/microstructures of SMPs and their fabrication, and to find suitable approaches for constructing SMP-based nano/microstructures for different applications. In this review, we summarize the current state of different SMP nano/microstructures, fabrication techniques, and applications, and give suggestions for their future development.
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Affiliation(s)
- Fenghua Zhang
- National Key Laboratory of Science and Technology on Advanced Composites in Special Enviroments, Harbin Institute of Technology (HIT), Harbin 150080, P. R. China.
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15
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Dugad R, Radhakrishna G, Gandhi A. Recent advancements in manufacturing technologies of microcellular polymers: a review. JOURNAL OF POLYMER RESEARCH 2020. [DOI: 10.1007/s10965-020-02157-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Chaithanya Vinay V, Mohan Varma DS. Fabrication and Testing of Auxetic Foams for Rehabilitation Applications. J Indian Inst Sci 2019. [DOI: 10.1007/s41745-019-00122-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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