1
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Raj SS, Mathew RM, Nair Y, S. T. A, T. P. V. Fabrication and Applications of Wrinkled Soft Substrates: An Overview. ChemistrySelect 2022. [DOI: 10.1002/slct.202200714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Soorya S. Raj
- Department of Chemistry CHRIST (Deemed to be University) Hosur Road Bangalore 560029 India
| | - Romina Marie Mathew
- Department of Chemistry CHRIST (Deemed to be University) Hosur Road Bangalore 560029 India
| | - Yamuna Nair
- Department of Chemistry CHRIST (Deemed to be University) Hosur Road Bangalore 560029 India
| | - Aruna S. T.
- Surface Engineering Division CSIR – National Aerospace Laboratories HAL Airport Road Bangalore 560017 India
| | - Vinod T. P.
- Department of Chemistry CHRIST (Deemed to be University) Hosur Road Bangalore 560029 India
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2
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Sinha M, Izadi A, Anthony R, Roccabianca S. A novel approach to finding mechanical properties of nanocrystal layers. NANOSCALE 2019; 11:7520-7526. [PMID: 30942804 DOI: 10.1039/c9nr02213a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Flexible, bendable, stretchable devices represent the future of electronics for a wide range of real-world applications. Due to the fact that these technologies deviate significantly from traditional wafer technologies there is a need to understand and engineer material systems that allow large elastic deformations present in such devices, which requires knowledge about the mechanical properties of these material systems. Here we evaluate the mechanical properties of a bilayer polydimethylsiloxane (PDMS)/silicon nanocrystal system. By observing the formation of instabilities due to finite bending deformation and applying theoretical modeling, we estimated the neo-Hookean coefficient (analogous to shear modulus at low stress/strain) of the silicon nanocrystal film to be 345 ± 23 kPa. The method used here represents a novel approach to evaluating these properties and is widely applicable to many different combinations of systems of nanocrystals and elastomers.
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Affiliation(s)
- Mayank Sinha
- Michigan State University, East Lansing, MI, USA.
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3
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Chambers LC, Huang Y, Jack KS, Blakey I. Spatial control of the topography of photo-sensitive block copolymer thin films. Polym Chem 2019. [DOI: 10.1039/c9py00200f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Spatially controlling self-assembly of block copolymer thin films through photoinduced molecular interactions that significantly impact on the glass transition temperature.
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Affiliation(s)
- Lewis C. Chambers
- Australian Institute for Bioengineering and Nanotechnology
- The University of Queensland
- Brisbane
- Australia
| | - Yun Huang
- Australian Institute for Bioengineering and Nanotechnology
- The University of Queensland
- Brisbane
- Australia
| | - Kevin S. Jack
- Centre for Microscopy and Microanalysis
- The University of Queensland
- Brisbane
- Australia
| | - Idriss Blakey
- Australian Institute for Bioengineering and Nanotechnology
- The University of Queensland
- Brisbane
- Australia
- Centre for Microscopy and Microanalysis
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4
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Schroeder TBH, Houghtaling J, Wilts BD, Mayer M. It's Not a Bug, It's a Feature: Functional Materials in Insects. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1705322. [PMID: 29517829 DOI: 10.1002/adma.201705322] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/15/2017] [Indexed: 05/25/2023]
Abstract
Over the course of their wildly successful proliferation across the earth, the insects as a taxon have evolved enviable adaptations to their diverse habitats, which include adhesives, locomotor systems, hydrophobic surfaces, and sensors and actuators that transduce mechanical, acoustic, optical, thermal, and chemical signals. Insect-inspired designs currently appear in a range of contexts, including antireflective coatings, optical displays, and computing algorithms. However, as over one million distinct and highly specialized species of insects have colonized nearly all habitable regions on the planet, they still provide a largely untapped pool of unique problem-solving strategies. With the intent of providing materials scientists and engineers with a muse for the next generation of bioinspired materials, here, a selection of some of the most spectacular adaptations that insects have evolved is assembled and organized by function. The insects presented display dazzling optical properties as a result of natural photonic crystals, precise hierarchical patterns that span length scales from nanometers to millimeters, and formidable defense mechanisms that deploy an arsenal of chemical weaponry. Successful mimicry of these adaptations may facilitate technological solutions to as wide a range of problems as they solve in the insects that originated them.
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Affiliation(s)
- Thomas B H Schroeder
- Department of Chemical Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI, 48109, USA
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Jared Houghtaling
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
- Department of Biomedical Engineering, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, MI, 48109, USA
| | - Bodo D Wilts
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Michael Mayer
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
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5
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Sun L, Riedel R, Stanciu SG, Yang F, Hampp N, Xu L, Wu A. Investigations on the elasticity of functional gold nanoparticles using single-molecule force spectroscopy. J Mater Chem B 2018; 6:2960-2971. [DOI: 10.1039/c7tb03309e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In this focused review we turn our attention towards several approaches for detecting the elasticity of NPs, systematically summarizing the divergent elasticity values of distinct gold nanoparticles (AuNPs) with different surfaces.
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Affiliation(s)
- Li Sun
- College of Science
- Nanjing Forestry University
- Nanjing
- P. R. China
- CAS Key Laboratory of Magnetic Materials and Devices & Key Laboratory of Additive Manufacturing Materials of Zhejiang Province & Division of Functional Materials and Nanodevices
| | - René Riedel
- Fachbereich Chemie
- Philipps Universität Marburg
- Marburg
- Germany
| | - Stefan G. Stanciu
- Center for Microscopy-Microanalysis and Information Processing
- University Politehnica of Bucharest
- Bucharest
- Romania
| | - Fang Yang
- CAS Key Laboratory of Magnetic Materials and Devices & Key Laboratory of Additive Manufacturing Materials of Zhejiang Province & Division of Functional Materials and Nanodevices
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
| | - Norbert Hampp
- Fachbereich Chemie
- Philipps Universität Marburg
- Marburg
- Germany
| | - Li Xu
- College of Science
- Nanjing Forestry University
- Nanjing
- P. R. China
| | - Aiguo Wu
- CAS Key Laboratory of Magnetic Materials and Devices & Key Laboratory of Additive Manufacturing Materials of Zhejiang Province & Division of Functional Materials and Nanodevices
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
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6
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Salmon AR, Parker RM, Groombridge AS, Maestro A, Coulston RJ, Hegemann J, Kierfeld J, Scherman OA, Abell C. Microcapsule Buckling Triggered by Compression-Induced Interfacial Phase Change. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:10987-10994. [PMID: 27700114 DOI: 10.1021/acs.langmuir.6b03011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
There is an emerging trend toward the fabrication of microcapsules at liquid interfaces. In order to control the parameters of such capsules, the interfacial processes governing their formation must be understood. Here, poly(vinyl alcohol) films are assembled at the interface of water-in-oil microfluidic droplets. The polymer is cross-linked using cucurbit[8]uril ternary supramolecular complexes. It is shown that compression-induced phase change causes the onset of buckling in the interfacial film. On evaporative compression, the interfacial film both increases in density and thickens, until it reaches a critical density and a phase change occurs. We show that this increase in density can be simply related to the film Poisson ratio and area compression. This description captures fundamentals of many compressive interfacial phase changes and can also explain the observation of a fixed thickness-to-radius ratio at buckling, [Formula: see text].
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Affiliation(s)
- Andrew R Salmon
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Richard M Parker
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Alexander S Groombridge
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Armando Maestro
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Roger J Coulston
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Jonas Hegemann
- Physics Department, TU Dortmund University , Otto-Hahn-Str 4, Dortmund 44221, Germany
| | - Jan Kierfeld
- Physics Department, TU Dortmund University , Otto-Hahn-Str 4, Dortmund 44221, Germany
| | - Oren A Scherman
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Chris Abell
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
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7
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Lv QR, Li HP, Lu CH, He XH. Computer Simulation of Thin Film Wrinkling on Elastic Substrate. CHINESE J CHEM PHYS 2016. [DOI: 10.1063/1674-0068/29/cjcp1512254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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8
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Zhang R, Lee B, Bockstaller MR, Douglas JF, Stafford CM, Kumar SK, Raghavan D, Karim A. Confined Pattern-Directed Assembly of Polymer-Grafted Nanoparticles in a Phase Separating Blend with a Homopolymer Matrix. Macromolecules 2016; 49:3965-3974. [PMID: 27524836 PMCID: PMC4979748 DOI: 10.1021/acs.macromol.6b00228] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The controlled organization of nanoparticle (NP) constituents into superstructures of well-defined shape, composition and connectivity represents a continuing challenge in the development of novel hybrid materials for many technological applications. We show that the phase separation of polymer-tethered nanoparticles immersed in a chemically different polymer matrix provides an effective and scalable method for fabricating defined submicron-sized amorphous NP domains in melt polymer thin films. We investigate this phenomenon with a view towards understanding and controlling the phase separation process through directed nanoparticle assembly. In particular, we consider isothermally annealed thin films of polystyrene-grafted gold nanoparticles (AuPS) dispersed in a poly(methyl methacrylate) (PMMA) matrix. Classic binary polymer blend phase separation related morphology transitions, from discrete AuPS domains to bicontinuous to inverse domain structure with increasing nanoparticle composition is observed, yet the kinetics of the AuPS/PMMA polymer blends system exhibit unique features compared to the parent PS/PMMA homopolymer blend. We further illustrate how to pattern-align the phase-separated AuPS nanoparticle domain shape, size and location through the imposition of a simple and novel external symmetry-breaking perturbation via soft-lithography. Specifically, submicron-sized topographically patterned elastomer confinement is introduced to direct the nanoparticles into kinetically controlled long-range ordered domains, having a dense yet well-dispersed distribution of non-crystallizing nanoparticles. The simplicity, versatility and roll-to-roll adaptability of this novel method for controlled nanoparticle assembly should make it useful in creating desirable patterned nanoparticle domains for a variety of functional materials and applications.
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Affiliation(s)
- Ren Zhang
- Department of Polymer Engineering, the University of Akron, Akron, OH 44325
| | - Bongjoon Lee
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 15213
| | - Michael R. Bockstaller
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 15213
| | - Jack F. Douglas
- Materials Science and Engineering Division, NIST, Gaithersburg, MD 20889
| | | | - Sanat K. Kumar
- Department of Chemical Engineering, Columbia University, 116th St & Broadway, New York, NY 10027
| | | | - Alamgir Karim
- Department of Polymer Engineering, the University of Akron, Akron, OH 44325
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9
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Lin H, Wang Y, Gan Y, Hou H, Yin J, Jiang X. Simultaneous Formation of a Self-Wrinkled Surface and Silver Nanoparticles on a Functional Photocuring Coating. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11800-11808. [PMID: 26471347 DOI: 10.1021/acs.langmuir.5b03484] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Bioinspired functional surface with micro/nanostructures are particularly attractive because of the potential for outstanding characteristics, such as self-cleaning, self-replenishing and antibiosis. Here, we presented a facile approach to fabricate a functional photocuring coating with both a self-wrinkling patterned surface and incorporated silver nanoparticles (Ag NPs). Fluorinated polymeric photoinitiator (FPPI) and silver precursor (TFAAg) can self-assemble together on the air/acrylate interface to form a top layer of photocuring liquid resin. Under UV irradiation, a wrinkled pattern was formed as a result of the mismatch in shrinkage caused by photopolymerization between the top layer and the bulk layer. Simultaneously, Ag NPs with sizes of 15 ± 8 nm in diameter were in situ generated in the photocuring coating through the photoreduction of TFAAg. Their number density is higher in the top layer than in the bulk. Scanning electron microscope (SEM) and atomic force microscope (AFM) measurements revealed that the characteristic wavelength (λ) and amplitude (A) of the wrinkled morphology increased with growing concentration of FPPI, and that the generation of Ag NPs led to the wrinkle-to-fold transition. Furthermore, the obtained functional coatings possess a low surface energy and self-replenishing and antibiosis capabilities as a result of the synergistic effect of the wrinkled surface covered by FPPI and Ag NPs.
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Affiliation(s)
- Hongbo Lin
- School of Chemistry & Chemical Engineering, State Key Laboratory for Metal Matrix Composite Materials, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China
| | - Yuanlong Wang
- State Key Laboratory of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd. , Shanghai 200436, People's Republic of China
| | - Yanchang Gan
- School of Chemistry & Chemical Engineering, State Key Laboratory for Metal Matrix Composite Materials, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China
| | - Honghao Hou
- School of Chemistry & Chemical Engineering, State Key Laboratory for Metal Matrix Composite Materials, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China
| | - Jie Yin
- School of Chemistry & Chemical Engineering, State Key Laboratory for Metal Matrix Composite Materials, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China
| | - Xuesong Jiang
- School of Chemistry & Chemical Engineering, State Key Laboratory for Metal Matrix Composite Materials, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China
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10
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Glatz BA, Tebbe M, Kaoui B, Aichele R, Kuttner C, Schedl AE, Schmidt HW, Zimmermann W, Fery A. Hierarchical line-defect patterns in wrinkled surfaces. SOFT MATTER 2015; 11:3332-3339. [PMID: 25803776 DOI: 10.1039/c5sm00318k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate a novel approach for controlling the formation of line-defects in wrinkling patterns by introducing step-like changes in the Young's modulus of elastomeric substrates supporting thin, stiff layers. Wrinkles are formed upon treating the poly(dimethylsiloxane) (PDMS) substrates by UV/Ozone (UVO) exposure in a uniaxially stretched state and subsequent relaxation. Line defects such as minutiae known from fingerprints are a typical feature in wrinkling patterns. The position where these defects occur is random for homogenous substrate elasticity and film thickness. However, we show that they can be predetermined by using PDMS substrates consisting of areas with different cross-linking densities. While changing the cross-linking density is well known to influence the wrinkling wavelength, we use this parameter in this study to force defect formation. The defect formation is monitored in situ using light microscopy and the mechanical parameters/film thicknesses are determined using imaging AFM indentation measurements. Thus the observed wrinkle-wavelengths can be compared to theoretical predictions. We study the density and morphology of defects for different changes in elasticity and compare our findings with theoretical considerations based on a generalized Swift-Hohenberg-equation to simply emulate the observed pattern-formation process, finding good agreement. The fact that for suitable changes in elasticity, well-ordered defect patterns are observed is discussed with respect to formation of hierarchical structures for applications in optics and nanotechnology.
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Affiliation(s)
- Bernhard A Glatz
- Department of Physical Chemistry II, University of Bayreuth, 95440 Bayreuth, Germany.
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11
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Rodríguez-Hernández J. Wrinkled interfaces: Taking advantage of surface instabilities to pattern polymer surfaces. Prog Polym Sci 2015. [DOI: 10.1016/j.progpolymsci.2014.07.008] [Citation(s) in RCA: 218] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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12
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Ye C, Tsukruk VV. Designing two-dimensional materials that spring rapidly into three-dimensional shapes. Science 2015; 347:130-1. [DOI: 10.1126/science.aaa2643] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Chunhong Ye
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Vladimir V. Tsukruk
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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13
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Hou J, Li Q, Han X, Lu C. Swelling/Deswelling-Induced Reversible Surface Wrinkling on Layer-by-Layer Multilayers. J Phys Chem B 2014; 118:14502-9. [DOI: 10.1021/jp508724n] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jing Hou
- School of Materials Science
and Engineering, Tianjin University, Tianjin 300072, P. R. China
| | - Qiaoyuan Li
- School of Materials Science
and Engineering, Tianjin University, Tianjin 300072, P. R. China
| | - Xue Han
- School of Materials Science
and Engineering, Tianjin University, Tianjin 300072, P. R. China
| | - Conghua Lu
- School of Materials Science
and Engineering, Tianjin University, Tianjin 300072, P. R. China
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14
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Geryak R, Tsukruk VV. Reconfigurable and actuating structures from soft materials. SOFT MATTER 2014; 10:1246-63. [PMID: 24651547 DOI: 10.1039/c3sm51768c] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The recent interest in reconfigurable soft materials may lead to the next paradigm in the development of adaptive and actuating materials and structures. Actuating soft materials eventually can be precisely designed to show stimuli-sensing, multi-length scale actuation, tunable transport, programmed shape control and multifunctional orthogonal responses. Herein, we discuss the various advances in the emerging field of reconfigurable soft materials with a focus on the various parameters that can be modulated to control a complex system behavior. In particular, we detail approaches that use either long-range fields (i.e. electrical, magnetic) or changes in local thermodynamic parameters (e.g., solvent quality) in order to elicit a precise dimensional and controlled response. The theoretical underpinnings and practical considerations for different approaches are briefly presented alongside several illustrative examples from the recent studies. In the end, we summarize recent accomplishments, critical issues to consider, and give perspectives on the developments of this exciting research field.
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Affiliation(s)
- Ren Geryak
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
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15
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Zhang Y, Dou R, Yang H, Wang J, Song Y. Water adhesion-tunable film prepared with morphology-controllable core/shell particles. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.01.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Yang Y, Han X, Ding W, Jiang S, Cao Y, Lu C. Controlled free edge effects in surface wrinkling via combination of external straining and selective O2 plasma exposure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:7170-7177. [PMID: 23705830 DOI: 10.1021/la4010517] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Herein the edge effect from the traction-free boundary condition is utilized to direct the spontaneous surface wrinkling. This boundary condition is attained by a simple combination of mechanical straining and selective exposure of polydimethylsiloxane (PDMS) substrate to O2 plasma (OP) through a copper grid. When the strained PDMS sheet is subjected to selective OP treatment, a patterned heterogeneous surface composed of the OP-exposed "hard" oxidized SiOx region (denoted as D1) and the OP-unexposed "soft" region (denoted as D2) is produced. The subsequent full release of the prestrain (ε(pre)) leads to the selective wrinkling in D1, rather than in D2. It is seen that even in D1, no wrinkling occurs in the vicinity of the D1 edge that is perpendicular to the wavevector. Furthermore, the average wrinkle wavelength in D1 (λ(D1)) is smaller than that of the exposed copper grid-free blank area (λ(blank)). This wavelength decrement between λ(D1) and λ(blank), which can be used to roughly estimate the edge-effect extent, increases with the applied mesh number of copper grids and exposure duration, while decreases with the increase of ε(pre). Meanwhile, there exists a decrease in the amplitude of the patterned wrinkles, when compared with that of the blank region. Additionally, hierarchical wrinkling is induced when the strain-free PDMS substrate is selectively exposed to OP, followed by uniaxial stretching and the subsequent blanket exposure. Consequently, oriented wrinkles perpendicular to the stretching direction are generated in D2. With respect to D1, no wrinkling happens or orthogonal wrinkles occur in this region depending on the applied mesh number, exposure duration, and ε(pre). In the above wrinkling process, the combinative edge effects in two perpendicular directions that are involved sequentially have been discussed.
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Affiliation(s)
- Yang Yang
- School of Materials Science and Engineering, Tianjin University, Tianjin 300072, P R China
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17
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Hu K, Gupta MK, Kulkarni DD, Tsukruk VV. Ultra-robust graphene oxide-silk fibroin nanocomposite membranes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:2301-2307. [PMID: 23450461 DOI: 10.1002/adma.201300179] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Indexed: 05/29/2023]
Affiliation(s)
- Kesong Hu
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, USA
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Lee I. Molecular self-assembly: smart design of surface and interface via secondary molecular interactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:2476-2489. [PMID: 23342993 DOI: 10.1021/la304123b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The molecular self-assembly of macromolecular species such as polymers, colloids, nano/microparticles, proteins, and cells when they interface with a solid/substrate surface has been studied for many years, especially in terms of molecular interactions, adsorption, and adhesion. Such fundamental knowledge is practically important in designing smart micro- and nanodevices and sensors, including biologically implantable ones. This review gives a brief sketch of molecular self-assembly and nanostructured multifunctional thin films that utilize secondary molecular interactions at surfaces and interfaces.
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Affiliation(s)
- Ilsoon Lee
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824-1226, USA.
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Yin J, Yagüe JL, Eggenspieler D, Gleason KK, Boyce MC. Deterministic order in surface micro-topologies through sequential wrinkling. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:5441-6. [PMID: 22915065 DOI: 10.1002/adma.201201937] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/17/2012] [Indexed: 05/11/2023]
Abstract
Ordered herringbone patterns with deterministic long and short wavelengths are created using a sequential wrinkling strategy (SWS). Patterns with a prescribed zig-zag turning angle less than 90° are obtained upon sequential wrinkling of non-equi-biaxial prestrain for the first time. SWS provides a new method for measuring thin-film mechanical properties simply through the wrinkling metrology without measurement of film thickness.
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Affiliation(s)
- Jie Yin
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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20
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Lisunova M, Holland N, Shchepelina O, Tsukruk VV. Template-assisted assembly of the functionalized cubic and spherical microparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13345-13353. [PMID: 22924760 DOI: 10.1021/la303096h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The patterned template-assisted assembly of the cubic microparticles driven by the competing capillary, Columbic, and van der Waals forces had been studied in comparison with the traditional spherical colloidal microparticles. We observed that the spherical and cubic microparticles assembled with different probability in the channels of the hydrophobic-hydrophilic patterned substrates due to differences in a balance of adhesive and capillary forces. In contrast to highly selective assembly of spherical microparticles, selective deposition of cubic microcrystals with channels is impeded by strong adhesive forces facilitated by large specific interfacial areas between cube facets and substrate. The modification of the patterned substrate by functionalized coatings with oppositely charged topmost layers significantly increases the probability (to 86%) of the cubic microparticles to assemble into chemically modified channels. The introduction of ultrathin LbL shells on cubic microparticles and functionalization of patterned substrates are critical for the directed colloidal assembly of anisotropic microparticles into ordered aggregates.
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Affiliation(s)
- Milana Lisunova
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Ni Y, Yang D, He L. Spontaneous wrinkle branching by gradient stiffness. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:031604. [PMID: 23030926 DOI: 10.1103/physreve.86.031604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Indexed: 06/01/2023]
Abstract
The concept of coherency loss is proposed to understand wrinkle branching as a pathway toward hierarchical wrinkling pattern formation in a compressed film-substrate system with gradient stiffness of the film or substrate. A simple model indicates that the wrinkle branching arises when the characteristic length of the stiffness inhomogeneity zone is larger than the coherency persistent length, which depends on the amplitude of the stiffness inhomogeneity. Numerical simulations of nonlinear wrinkles based on the model of the Föppl-von Kármán plate on compliant substrates show how regulating the size and amplitude of the stiffness inhomogeneities results in branched wrinkles in striking agreement with the existing observations. The paper reveals the origin of such kinds of branched wrinkles and may provide a guideline for controllable hierarchical wrinkles by patterning the stiffness gradient.
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Affiliation(s)
- Yong Ni
- Department of Modern Mechanics, CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
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22
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Guo CF, Nayyar V, Zhang Z, Chen Y, Miao J, Huang R, Liu Q. Path-guided wrinkling of nanoscale metal films. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:3010-3076. [PMID: 22553132 DOI: 10.1002/adma.201200540] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 03/20/2012] [Indexed: 05/31/2023]
Affiliation(s)
- Chuan Fei Guo
- National Center for Nanoscience and Technology No. 11 Beiyitiao, Zhongguancun, Beijing 100190, China
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23
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Bao Y, Vigderman L, Zubarev ER, Jiang C. Robust multilayer thin films containing cationic thiol-functionalized gold nanorods for tunable plasmonic properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:923-30. [PMID: 22103248 DOI: 10.1021/la203993m] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Gold nanorods have great potential in a variety of applications because of their unique physical properties. In this article, we present the layer-by-layer (LbL) assembly of thin films containing positively charged gold nanorods that are covalently functionalized by cationic thiol molecules. The cationic gold nanorods are uniformly distributed in ultrathin nanocomposite LbL thin films. We studied the collective surface plasmon resonance coupling in the LbL films via UV-visible spectroscopy and evaluated their application in the surface-enhanced Raman scattering detection of rhodamine 6G probe molecules. Furthermore, we successfully manufactured freestanding nanoscale thin films containing multilayers of gold nanorods with a total thickness of less than 50 nm. The surface morphology and their optical and mechanical properties were systematically investigated, and the polycationic gold nanorods were found to play an important role in manipulating the properties of the nanocomposite thin films. Our findings reveal that such nanorods are excellent building blocks for constructing functional LbL films with tunable plasmonic behavior and robust mechanical properties.
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Affiliation(s)
- Ying Bao
- Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
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24
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Addition of silica nanoparticles to tailor the mechanical properties of nanofibrillated cellulose thin films. J Colloid Interface Sci 2011; 363:566-72. [DOI: 10.1016/j.jcis.2011.07.085] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Revised: 07/25/2011] [Accepted: 07/27/2011] [Indexed: 11/17/2022]
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25
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Lisunova MO, Drachuk I, Shchepelina OA, Anderson KD, Tsukruk VV. Direct probing of micromechanical properties of hydrogen-bonded layer-by-layer microcapsule shells with different chemical compositions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:11157-11165. [PMID: 21800830 DOI: 10.1021/la202082w] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The mechanical properties of hydrogen-bonded layer-by-layer (LbL) microcapsule shells constructed from tannic acid (TA) and poly(vinylpyrrolidone) (PVPON) components have been studied in both the dry and swollen states. In the dry state, the value of the elastic modulus was measured to be within 0.6-0.7 GPa, which is lower than the typical elastic modulus for electrostatically assembled LbL shells. Threefold swelling of the LbL shells in water results in a significant reduction of the elastic modulus to values well below 1 MPa, which is typical value seen for highly compliant gel materials. The increase of the molecular weight of the PVPON component from 55 to 1300 kDa promotes chain entanglements and causes a stiffening of the LbL shells with a more than 2-fold increase in elastic modulus value. Moreover, adding a polyethylenimine prime layer to the LbL shell affects the growth of hydrogen-bonded multilayers which consequently results in dramatically stiffer, thicker, and rougher LbL shells with the elastic modulus increasing by more than an order of magnitude, up to 4.3 MPa. An alternation of the elastic properties of very compliant hydrogen-bonded shells by variation of molecular weight is a characteristic feature of weakly bonded LbL shells. Such an ability to alter the elastic modulus in a wide range is critically important for the design of highly compliant microcapsules with tunable mechanical stability, loading ability, and permeability.
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Affiliation(s)
- Milana O Lisunova
- School of Material Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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26
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Yu Q, Huang H, Peng X, Ye Z. Ultrathin free-standing close-packed gold nanoparticle films: conductivity and Raman scattering enhancement. NANOSCALE 2011; 3:3868-3875. [PMID: 21837336 DOI: 10.1039/c1nr10578g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A simple filtration technique was developed to prepare large scale free-standing close-packed gold nanoparticle ultrathin films using metal hydroxide nanostrands as both barrier layer and sacrificial layer. As thin as 70 nm, centimeter scale robust free-standing gold nanoparticle thin film was obtained. The thickness of the films could be easily tuned by the filtration volumes. The electronic conductivities of these films varied with the size of the gold nanoparticles, post-treatment temperature, and thickness, respectively. The conductivity of the film prepared from 20 nm gold nanoparticles is higher than that of the film prepared from 40 nm gold nanoparticle by filtering the same filtration volume of their solution, respectively. Their conductivities are comparable to that of the 220 nm thick ITO film. Furthermore, these films demonstrated an average surface Raman scattering enhancement up to 6.59 × 10(5) for Rhodamine 6 G molecules on the film prepared from 40 nm gold nanoparticles. Due to a lot of nano interspaces generated from the close-packed structures, two abnormal enhancements and relative stronger intensities of the asymmetrical vibrations at 1534 and 1594 cm(-1) of R6G were observed, respectively. These robust free-standing gold nanoparticle films could be easily transferred onto various solid substrates and hold the potential application for electrodes and surface enhanced Raman detectors. This method is applicable for preparation of other nanoparticle free-standing thin films.
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Affiliation(s)
- Qing Yu
- State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, P. R. China
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27
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Chung JY, Nolte AJ, Stafford CM. Surface wrinkling: a versatile platform for measuring thin-film properties. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:349-68. [PMID: 20814918 DOI: 10.1002/adma.201001759] [Citation(s) in RCA: 273] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Indexed: 05/04/2023]
Abstract
Surface instabilities in soft matter have been the subject of increasingly innovative research aimed at better understanding the physics of their formation and their utility in patterning, organizing, and measuring materials properties on the micro and nanoscale. The focus of this Review is on a type of instability pattern known as surface wrinkling, covering the general concepts of this phenomenon and several recent applications involving the measurement of thin-film properties. The ability of surface wrinkling to yield new insights into particularly challenging materials systems such as ultrathin films, polymer brushes, polyelectrolyte multilayer assemblies, ultrasoft materials, and nanoscale structured materials is highlighted. A perspective on the future directions of this maturing field, including the prospects for advanced thin-film metrology methods, facile surface patterning, and the control of topology-sensitive phenomena, such as wetting and adhesion, is also presented.
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Affiliation(s)
- Jun Young Chung
- Polymers Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA
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28
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Kharlampieva E, Kozlovskaya V, Wallet B, Shevchenko VV, Naik RR, Vaia R, Kaplan DL, Tsukruk VV. Co-cross-linking silk matrices with silica nanostructures for robust ultrathin nanocomposites. ACS NANO 2010; 4:7053-7063. [PMID: 21090657 DOI: 10.1021/nn102456w] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report on a novel assembly approach to fabricate ultrathin robust freely standing nanocomposite membranes. The materials are composed of a pre-cross-linked silk fibroin matrix with incorporated silica nanoparticles with silsesquioxane cores (POSS) or clay nanoplatelets. These reinforced silk membranes have enhanced mechanical properties as compared to traditional silk-based nanocomposites reported previously. Up to 6-fold and 8-fold increase in elastic modulus and toughness, respectively, were found for these nanocomposites. In contrast, traditional LbL-assembled nanocomposites showed only a 3-fold increase in mechanical strength. The silk nanocomposites obtained also revealed excellent optical transparency in the visible region especially if reinforced with POSS nanoparticles, which suggests their utility as low cost, nontoxic, and easily scalable reinforced biomaterials for mechanically demanding applications.
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Affiliation(s)
- Eugenia Kharlampieva
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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29
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Brito WH, Silva RA, Miwa RH. Gold adatoms and clusters on PPV: An ab initio investigation. J Chem Phys 2010; 133:204703. [PMID: 21133448 DOI: 10.1063/1.3506771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have performed an ab initio investigation of the energetic, structural, electronic, and vibrational properties of Au atoms and clusters adsorbed on poly-p-phenylene vinylene (PPV) chains, Au(n)/PPV (with n = 1, 2, 6, 7, 10, and 12). We find that the Au(n)/PPV systems are energetically stable by 0.5 eV, compared with the isolated systems, viz., PPV chain and Au(n) clusters, thus supporting the formation of Au(n)/PPV nanocomposites. Further support to the formation of Au(n)/PPV has been provided by examining the vibrational properties of pristine PPV and Au(n)/PPV systems. In agreement with experimental measurements, we find a reduction on the in-plane vibrational frequency of C-C bonds of Au(n)/PPV, when compared with the same vibrational modes of pristine PPV. The electronic properties of isolated Au(n) clusters are modified when adsorbed on PPV. The highest occupied states of Au(n)/PPV are mostly concentrated on the Au(n) cluster, while the lowest unoccupied states are mainly localized along the PPV chain. The HOMO-LUMO energy gap of the Au(n)/PPV systems are smaller than the energy gap of the isolated systems, Au(n) clusters, and pristime PPV chains.
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Affiliation(s)
- W H Brito
- Instituto de Física, Universidade Federal de Uberlândia, C. P. 593, 38400-902 Uberlândia, MG, Brazil
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30
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Kulkarni DD, Choi I, Singamaneni SS, Tsukruk VV. Graphene oxide--polyelectrolyte nanomembranes. ACS NANO 2010; 4:4667-4676. [PMID: 20669898 DOI: 10.1021/nn101204d] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Owing to its remarkable electrical, thermal, and mechanical properties, graphene, an atomic layer of carbon, is considered to be an excellent two-dimensional filler for polymer nanocomposites with outstanding mechanical strength along with the potential for excellent electrical and thermal properties. One of the critical limitations with conventional fillers is that the loading fraction required for achieving significant improvement in mechanical properties is relatively high, frequently reaching 50% for maximum strength. Here, we demonstrate that the mechanical properties of ultrathin laminated nanocomposites can be significantly enhanced by the incorporation of small amounts of a dense monolayer of planar graphene oxide (GO) flakes. Negatively charged functionalized graphene oxide layers were incorporated into polyelectrolyte multilayers (PEMs) fabricated in a layer-by-layer (LbL) assembly via Langmuir-Blodgett (LB) deposition. These LbL-LB graphene oxide nanocomposite films were released as robust freely standing membranes with large lateral dimensions (centimeters) and a thickness of around 50 nm. Micromechanical measurements showed enhancement of the elastic modulus by an order of magnitude, from 1.5 GPa for pure LbL membranes to about 20 GPa for only 8.0 vol % graphene oxide encapsulated LbL membranes. These tough nanocomposite PEMs can be freely suspended over large (few millimeters) apertures and sustain large mechanical deformations.
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Affiliation(s)
- Dhaval D Kulkarni
- School of Material Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, USA
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31
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McConney ME, Singamaneni S, Tsukruk VV. Probing Soft Matter with the Atomic Force Microscopies: Imaging and Force Spectroscopy. POLYM REV 2010. [DOI: 10.1080/15583724.2010.493255] [Citation(s) in RCA: 172] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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32
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Singamaneni S, McConney ME, Tsukruk VV. Swelling-induced folding in confined nanoscale responsive polymer gels. ACS NANO 2010; 4:2327-2337. [PMID: 20232813 DOI: 10.1021/nn901886y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Mechanical instabilities such as buckling, wrinkling, creasing, and folding are commonplace in both natural and synthetic systems over a wide range of length scales. In this study, we focus on the spontaneous folding behavior of the highly swellable confined nanoscale (thickness below 100 nm) gel films resulting in the formation of a network of regularly folded structures spontaneously emerging in the course of their swelling and drying. We suggest that regular self-folding is originated from periodic instabilities (wrinkles) caused by swelling-initiated stresses under confined conditions. Furthermore, folded gel structures can be organized into regular serpentine-like manner by imposing various boundary conditions on microimprinted surfaces. We suggest that this demonstration of uniform gel to mechanically mediate morphogenesis has far-reaching implications in the creation of complex, large-area, 3D gel nanostructures.
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Affiliation(s)
- Srikanth Singamaneni
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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33
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Singamaneni S, McConney ME, Tsukruk VV. Spontaneous self-folding in confined ultrathin polymer gels. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:1263-1268. [PMID: 20437516 DOI: 10.1002/adma.200903052] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- Srikanth Singamaneni
- School of Materials Science and Engineering, Georgia Institute of Technology Atlanta, GA 30318, USA
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34
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Chung JY, Chastek TQ, Fasolka MJ, Ro HW, Stafford CM. Quantifying residual stress in nanoscale thin polymer films via surface wrinkling. ACS NANO 2009; 3:844-852. [PMID: 19298053 DOI: 10.1021/nn800853y] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Residual stress, a pervasive consequence of solid materials processing, is stress that remains in a material after external forces have been removed. In polymeric materials, residual stress results from processes, such as film formation, that force and then trap polymer chains into nonequilibrium stressed conformations. In solvent-cast films, which are central to a wide range of technologies, residual stress can cause detrimental effects, including microscopic defect formation and macroscopic dimensional changes. Since residual stress is difficult to measure accurately, particularly in nanoscale thin polymer films, it remains a challenge to understand and control. We present here a quantitative method of assessing residual stress in polymer thin films by monitoring the onset of strain-induced wrinkling instabilities. Using this approach, we show that thin (>100 nm) polystyrene films prepared via spin-coating possess residual stresses of approximately 30 MPa, close to the crazing and yield stress. In contrast to conventional stress measurement techniques such as wafer curvature, our technique has the resolution to measure residual stress in films as thin as 25 nm. Furthermore, we measure the dissipation of residual stress through two relaxation mechanisms: thermal annealing and plasticizer addition. In quantifying the amount of residual stress in these films, we find that the residual stress gradually decreases with increasing annealing time and plasticizer amounts. Our robust and simple route to measure residual stress adds a key component to the understanding of polymer thin film behavior and will enable identification of more effective processing routes that mitigate the detrimental effects of residual stress.
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Affiliation(s)
- Jun Young Chung
- Polymers Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, USA
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35
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36
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Selective surface modification of free-standing polysaccharide nanosheet with micro/nano-particles identified by structural color changes. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2008.09.056] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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37
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Schweikart A, Horn A, Böker A, Fery A. Controlled Wrinkling as a Novel Method for the Fabrication of Patterned Surfaces. COMPLEX MACROMOLECULAR SYSTEMS I 2009. [DOI: 10.1007/12_2009_22] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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38
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Singamaneni S, Bertoldi K, Chang S, Jang JH, Thomas EL, Boyce MC, Tsukruk VV. Instabilities and pattern transformation in periodic, porous elastoplastic solid coatings. ACS APPLIED MATERIALS & INTERFACES 2009; 1:42-47. [PMID: 20355751 DOI: 10.1021/am800078f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Pattern transformation in periodic microporous elastoplastic solid coatings is caused by a buckling of the struts and a rotation of the nodes under compressive stresses. The results of a nonlinear numerical investigation confirm the critical role of the bifurcation of the periodic solid under compressive stresses. In striking contrast to the earlier observations of elastic instabilities in porous elastomeric solids, the elastic-plastic nature of the cross-linked periodic microstructure studied here provides the ability to lock in the transformed pattern with complete relaxation of the internal stresses. The study unveils a novel deformation mode in porous periodic solids in the form of organized buckling instability of weak strut elements.
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Zimnitsky D, Shevchenko VV, Tsukruk VV. Perforated, freely suspended layer-by-layer nanoscale membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:5996-6006. [PMID: 18457436 DOI: 10.1021/la7038575] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Ultrathin, perforated, and freely suspended membranes with uniform nanopores in the range of tens of nanometers have been fabricated using a fast, simple method of spin-assisted layer-by-layer assembly on hydrophobic substrates. Membranes with thicknesses down to 20 nm were robust enough to be released from the sacrificial substrates, transferred onto various surfaces, and suspended over microscopic openings. The nanopore size can be controlled by tuning the number of polyelectrolyte bilayers, spinning speed, and a proper selection of hydrophobic substrates. We demonstrate that the formation of nanopores is caused by the partial dewetting of polyelectrolyte layers in the course of their deposition on the underlying hydrophobic surfaces. The nanoscale thickness of perforated membranes with relatively uniform size and a high concentration of nanopores provides perspectives for higher rates of transport through freely suspended LbL membranes. The highly perforated LbL membranes introduced here can serve as a novel platform for ultrafine separation considering an intriguing combination of nanopores, nanoscale membrane thickness, and easy functionalization.
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Affiliation(s)
- Dmitry Zimnitsky
- Georgia Institute of Technology, School of Materials Science and Engineering, Atlanta, Georgia 30332, USA
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40
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Zhang Y, Matsumoto EA, Peter A, Lin PC, Kamien RD, Yang S. One-Step Nanoscale Assembly of Complex Structures via Harnessing of an Elastic Instability. NANO LETTERS 2008; 8:1192-1196. [PMID: 18333622 DOI: 10.1021/nl0801531] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report on a simple yet robust method to produce orientationally modulated two-dimensional patterns with sub-100 nm features over cm2 regions via a solvent-induced swelling instability of an elastomeric film with micrometer-scale perforations. The dramatic reduction of feature size ( approximately 10 times) is achieved in a single step, and the process is reversible and repeatable without the requirement of delicate surface preparation or chemistry. By suspending ferrous and other functional nanoparticles in the solvent, we have faithfully printed the emergent patterns onto flat and curved substrates. We model this elastic instability in terms of elastically interacting "dislocation dipoles" and find complete agreement between the theoretical ground-state and the observed pattern. Our understanding allows us to manipulate the structural details of the membrane to tailor the elastic distortions and generate a variety of nanostructures.
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Affiliation(s)
- Ying Zhang
- Laboratory for Research on the Structure of Matter, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA 19104, USA
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41
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Surface patterns induced by laser irradiation on thin polymer bilayer films. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2007.06.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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42
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Takeoka S, Okamura Y, Fujie T, Fukui Y. Development of biodegradable nanosheets as nanoadhesive plaster. PURE APPL CHEM 2008. [DOI: 10.1351/pac200880112259] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sheet-shaped carriers having both obverse and reverse surfaces (thus, a large contact area for targeting a site and adhesive properties without any chemical cross-linker onto tissue surface) have several advantages as surgical dressings. These advantages include active targeting over spherically shaped carriers, which thus have an extremely small contact area for targeting sites. Here, we propose a novel methodology for preparation of a free-standing, ultra-thin, and biocompatible polymer nanosheet having heterosurfaces, fabricated through macromolecular assembly. In the context of biomedical applications, the targeted properties include injectable sheet-shaped drug carriers having precisely controlled size by exploiting micropatterned substrate, and giant polymer nanosheets composed of biocompatible polysaccharides. A huge aspect ratio, in excess of 106, is particularly applicable for novel surgical dressings. These biocompatible polymer nanosheets having heterosurfaces can thus be regarded as new biomaterials for minimally invasive treatment.
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Affiliation(s)
- Shinji Takeoka
- 1Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, Tokyo, 169-8555, Japan
| | - Yosuke Okamura
- 2Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 169-8555, Japan
| | - Toshinori Fujie
- 2Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 169-8555, Japan
| | - Yoshihito Fukui
- 2Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 169-8555, Japan
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Lu C, Möhwald H, Fery A. A lithography-free method for directed colloidal crystal assembly based on wrinkling. SOFT MATTER 2007; 3:1530-1536. [PMID: 32900109 DOI: 10.1039/b712706e] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A simple, novel, and completely lithography-free assembly strategy is reported for directed colloidal crystal assembly on optically transparent substrates. The templates are stable, well-controlled relaxation-wrinkles of ultrathin multilayer films in a non-stretched state, which are fabricated by layer-by-layer self-assembly of polymeric films on soft elastomeric substrates followed by uniaxial plastic deformations. The results show that the wrinkles can be used efficiently to topographically direct colloidal crystal assembly in dip coating. Remarkably highly regular 1- and 2-dimensional patterned colloidal crystals with controlled structures have been obtained. Furthermore, the concept is rather universal and applicable to various particle types provided surface interactions between particles and template are suitable.
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Affiliation(s)
- Conghua Lu
- Interface Department, Max Planck Institute of Colloids and Interfaces, Potsdam, 14424, Germany
| | - Helmuth Möhwald
- Interface Department, Max Planck Institute of Colloids and Interfaces, Potsdam, 14424, Germany
| | - Andreas Fery
- Interface Department, Max Planck Institute of Colloids and Interfaces, Potsdam, 14424, Germany and Department of Physical Chemistry, University of Bayreuth, 95440, Germany.
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Zimnitsky D, Jiang C, Xu J, Lin Z, Zhang L, Tsukruk VV. Photoluminescence of a freely suspended monolayer of quantum dots encapsulated into layer-by-layer films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:10176-83. [PMID: 17725371 DOI: 10.1021/la7014644] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A single monolayer of CdSe/ZnS quantum dots (QDs) has been encapsulated into a 60 nm free-suspended layer-by-layer (LbL) film. The QD monolayer showed a low light-emission within this film in contact with supporting solid substrates, but the manifold increase of photoluminescencence intensity was observed when the film was lifted and freely suspended over the microfabricated cylindrical cavities. This phenomenon was discussed in relationship with the effect of the elimination of the surface quenching enhanced by optical reflection from highly reflective silicon cavities. We suggest that a significant increase of the photoluminescence intensity of QD monolayers suspended over the microfabricated array can be interesting for future diagnostic and sensing applications.
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Affiliation(s)
- Dmitry Zimnitsky
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Zimnitsky D, Jiang C, Xu J, Lin Z, Tsukruk VV. Substrate- and time-dependent photoluminescence of quantum dots inside the ultrathin polymer LbL film. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:4509-15. [PMID: 17346070 DOI: 10.1021/la0636917] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The photoluminescence of CdSe/ZnS quantum dots (QDs) in different configurations at solid surfaces (glass, silicon, PDMS, and metals) is considered for three types of organization: QDs directly adsorbed on solid surfaces, separated from the solid surface by a nanoscale polymer film with different thickness, and encapsulated into a polymer film. The complete suppression of photoluminescence for QDs on conductive metal surfaces (copper, gold) indicated a strong quenching effect. The temporal variation of the photoluminescent intensity on other substrates (glass, silicon, and PDMS) can be tuned by placing the nanoscale (3-50 nm) LbL polymer film between QDs and the substrate. The photooxidation and photobleaching processes of QD nanoparticles in the vicinity of the solid surface can be tuned by proper selection of the substrate and the dielectric nanoscale polymer film placed between the substrate and QDs. Moreover, the encapsulation of QD nanoparticles into the polymer film resulted in a dramatic initial increase in the photoemission intensity due to the accelerated photooxidation process. The phenomenon of enhanced photoemission of QDs encapsulated into the ultrathin polymer film provides not only the opportunity for making flexible, ultrathin, QD-containing polymer films, transferable to any microfabricated substrate, but also improved light emitting properties.
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Affiliation(s)
- Dmitry Zimnitsky
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Lin YH, Jiang C, Xu J, Lin Z, Tsukruk VV. Robust, fluorescent, and nanoscale freestanding conjugated films. SOFT MATTER 2007; 3:432-436. [PMID: 32900062 DOI: 10.1039/b617343h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The fabrication of free-standing structures of nanoscale thickness is technically challenging because of the poor mechanical stability of conventional polymers. Conjugated polymers (CP) composed of rod-like chains with much stronger mechanical properties are exploited here for layer-by-layer assembly. We successfully fabricated ultrathin freestanding layer-by-layer conjugated films (under 20 nm thick) which are flexible, easily fabricated, and demonstrated excellent mechanical properties combined with high fluorescence. This unique combination of properties can be considered for new applications such as flexible, lightweight displays and large luminescent panels.
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Affiliation(s)
- Yen-Hsi Lin
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA. and Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011, USA.
| | - Chaoyang Jiang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
| | - Jun Xu
- Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011, USA.
| | - Zhiqun Lin
- Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011, USA.
| | - Vladimir V Tsukruk
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
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Watanabe H, Vendamme R, Kunitake T. Development of Fabrication of Giant Nanomembranes. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2007. [DOI: 10.1246/bcsj.80.433] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Vendamme R, Ohzono T, Nakao A, Shimomura M, Kunitake T. Synthesis and micromechanical properties of flexible, self-supporting polymer-SiO2 nanofilms. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:2792-9. [PMID: 17253729 DOI: 10.1021/la062084g] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Large-scale, self-supporting ultrathin films composed of an elastomeric polyacrylate network interpenetrated by a silica (SiO2) network were synthesized and characterized. The organic network was first photopolymerized and the silica structure was subsequently developed in situ in the preformed organic gel. Composition and morphology of the hybrid interpenetrated network (IPN) nanofilms were characterized by infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy and compared with the case of zirconia (ZrO2) hybrid IPN reported earlier. Young modulus, ultimate tensile strength, and ultimate tensile elongation were determined for different organic/inorganic molar ratios and give some insights on how the composition of the nanofilms influence their robustness and self-supporting properties.
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Affiliation(s)
- Richard Vendamme
- Topochemical Design Laboratory, Frontier Research System (FRS), The Institute of Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako-shi, Saitama, 351-0198 Japan
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Hendricks TR, Lee I. Wrinkle-free nanomechanical film: control and prevention of polymer film buckling. NANO LETTERS 2007; 7:372-9. [PMID: 17298003 DOI: 10.1021/nl062544q] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
For the first time, we report on methods to control and prevent polymer films from buckling. Buckled morphologies were created by thermally cycling or mechanically compressing a poly(dimethylsiloxane) substrate coated with a polyelectrolyte multilayer film. By variation of the dimensions of the surface topography relative to the buckling wavelength (e.g., pattern size is less than, equal to, and greater than the buckling wavelength), the orientation and the local morphology of the buckled films were controlled. On the basis of the information obtained, we demonstrate how to alleviate the unavoidable buckling by incorporating nanoparticles into the film. In addition, we studied the effect of the silica layer that results from oxygen plasma treatment and the critical temperature for permanent film buckling.
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Affiliation(s)
- Troy R Hendricks
- Department of Chemical Engineering and Materials Science, Michigan State University, 2527 Engineering, East Lansing, Michigan 48824, USA
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