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Monnier X, Marina S, Lopez de Pariza X, Sardón H, Martin J, Cangialosi D. Physical Aging Behavior of a Glassy Polyether. Polymers (Basel) 2021; 13:954. [PMID: 33804594 PMCID: PMC8003685 DOI: 10.3390/polym13060954] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 11/16/2022] Open
Abstract
The present work aims to provide insights on recent findings indicating the presence of multiple equilibration mechanisms in physical aging of glasses. To this aim, we have investigated a glass forming polyether, poly(1-4 cyclohexane di-methanol) (PCDM), by following the evolution of the enthalpic state during physical aging by fast scanning calorimetry (FSC). The main results of our study indicate that physical aging persists at temperatures way below the glass transition temperature and, in a narrow temperature range, is characterized by a two steps evolution of the enthalpic state. Altogether, our results indicate that the simple old-standing view of physical aging as triggered by the α relaxation does not hold true when aging is carried out deep in the glassy state.
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Affiliation(s)
- Xavier Monnier
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain;
| | - Sara Marina
- POLYMAT, University of the Basque Country UPV/EHU, Av. de Tolosa 72, 20018 San Sebastián, Spain; (S.M.); (X.L.d.P.); (H.S.); (J.M.)
| | - Xabier Lopez de Pariza
- POLYMAT, University of the Basque Country UPV/EHU, Av. de Tolosa 72, 20018 San Sebastián, Spain; (S.M.); (X.L.d.P.); (H.S.); (J.M.)
| | - Haritz Sardón
- POLYMAT, University of the Basque Country UPV/EHU, Av. de Tolosa 72, 20018 San Sebastián, Spain; (S.M.); (X.L.d.P.); (H.S.); (J.M.)
| | - Jaime Martin
- POLYMAT, University of the Basque Country UPV/EHU, Av. de Tolosa 72, 20018 San Sebastián, Spain; (S.M.); (X.L.d.P.); (H.S.); (J.M.)
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
- Centro de Investigacións Tecnolóxicas, Universidade da Coruña, Campus de Esteiro s/n, 15403 Ferrol, Spain
| | - Daniele Cangialosi
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain;
- Centro de Fisica de Materiales (CSIC-UPV/EHU) Paseo Manuel de Lardizabal 5, 20018 Sebastián, Spain
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2
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Fan X, Xu J, Chen L, Hong N, Wang C, Ma J, Ma Y. Processing Induced Nonequilibrium Behavior of Polyvinylpyrrolidone Nanofilms Revealed by Dewetting. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:15430-15441. [PMID: 33306375 DOI: 10.1021/acs.langmuir.0c03098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Polyvinylpyrrolidone (PVP) nanofilms prepared by spin-coating have vast applications in biological and microdevice fields. However, detailed knowledge of processing induced nonequilibrium behavior of PVP nanofilms and solutions for minimizing residual stresses toward high-quality films has still been lacking. In the present study, we first explored the rapid film formation process via statistics on nascent holes. Next, by employing dewetting as a major probe, we revealed that many processing conditions, particularly previously overlooked variables like the atmosphere, substrates, and immersion time, were correlated substantially with the degree of nonequilibrium of nanofilms. Proper aging temperature and time were demonstrated essential for releasing residual stresses and achieving more equilibrium nanofilms. This work offered abundant experimental evidence in the building relationship between the processing and nonequilibrium nature of polymer nanofilms, which were crucial for their preparation and application.
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Affiliation(s)
- Xiao Fan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Jiao Xu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Long Chen
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Ning Hong
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Chuanbo Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Jinghong Ma
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Yu Ma
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
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3
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Mulama AA, Roumpos K, Pradipkanti L, Oduor AO, Reiter G. Rheological Properties of Blends of Isotactic Polystyrene–Isotactic Poly( para-methylstyrene) Films Derived from a Comparative Dewetting Study. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Austine A. Mulama
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
- Department of Physics and Materials Science, School of Physical and Biological Sciences, Maseno University, 333, 40105 Maseno, Kenya
| | - Konstantinos Roumpos
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
| | - L. Pradipkanti
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
| | - Andrew O. Oduor
- Department of Physics and Materials Science, School of Physical and Biological Sciences, Maseno University, 333, 40105 Maseno, Kenya
| | - Günter Reiter
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
- Freiburg Center for Interactive Materials and Bio-inspired Technologies (FIT), Albert-Ludwigs-Universität, Freiburg 79110, Germany
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4
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5
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Mulama AA, Chandran S, Roumpos K, Oduor AO, Reiter G. Dewetting Rheology for Determining Viscoelastic Properties of Nonequilibrated Thin Polymer Films. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01384] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Austine A. Mulama
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
- Department of Physics and Materials Science, School of Biological and Physical Sciences, Maseno University, PO Box 333-40105, Maseno, Kenya
| | - Sivasurender Chandran
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
| | - Konstantinos Roumpos
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
| | - Andrew O. Oduor
- Department of Physics and Materials Science, School of Biological and Physical Sciences, Maseno University, PO Box 333-40105, Maseno, Kenya
| | - Günter Reiter
- Physikalisches Institut, Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg 79104, Germany
- Freiburg Center for Interactive Materials and Bio-inspired Technologies (FIT), Albert-Ludwigs-Universität, Freiburg 79110, Germany
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6
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Cheng X, Böker A, Tsarkova L. Temperature-Controlled Solvent Vapor Annealing of Thin Block Copolymer Films. Polymers (Basel) 2019; 11:E1312. [PMID: 31390732 PMCID: PMC6722758 DOI: 10.3390/polym11081312] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/01/2019] [Accepted: 08/03/2019] [Indexed: 12/05/2022] Open
Abstract
Solvent vapor annealing is as an effective and versatile alternative to thermal annealing to equilibrate and control the assembly of polymer chains in thin films. Here, we present scientific and practical aspects of the solvent vapor annealing method, including the discussion of such factors as non-equilibrium conformational states and chain dynamics in thin films in the presence of solvent. Homopolymer and block copolymer films have been used in model studies to evaluate the robustness and the reproducibility of the solvent vapor processing, as well as to assess polymer-solvent interactions under confinement. Advantages of utilizing a well-controlled solvent vapor environment, including practically interesting regimes of weakly saturated vapor leading to poorly swollen states, are discussed. Special focus is given to dual temperature control over the set-up instrumentation and to the potential of solvo-thermal annealing. The evaluated insights into annealing dynamics derived from the studies on block copolymer films can be applied to improve the processing of thin films of crystalline and conjugated polymers as well as polymer composite in confined geometries.
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Affiliation(s)
- Xiao Cheng
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476 Potsdam-Golm, Germany
- Lehrstuhl für Polymermaterialien und Polymertechnologie, University of Potsdam, 14476 Potsdam-Golm, Germany
| | - Alexander Böker
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476 Potsdam-Golm, Germany
- Lehrstuhl für Polymermaterialien und Polymertechnologie, University of Potsdam, 14476 Potsdam-Golm, Germany
| | - Larisa Tsarkova
- Deutsches Textilforschungszentrum Nord-West (DNTW), Adlerstr. 1, 47798 Krefeld, Germany.
- Chair of Colloid Chemistry, Department of Chemistry, Moscow State University, Leninskie Gory 1-3, 119991 Moscow, Russia.
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7
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Xu J, Zhang H, Li J, Zhang L, Zuo B, Tsui OKC, Wang X. Conformation-Sensitive Surface Dynamics in Thin Poly(ethylene terephthalate) Film. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02284] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Jianquan Xu
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Haosong Zhang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jiachen Li
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Li Zhang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Biao Zuo
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Ophelia K. C. Tsui
- Department of Physics, Hong Kong University of Science & Technology, Clear Water Bay, Hong Kong, China
| | - Xinping Wang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
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8
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Kchaou M, Alcouffe P, Chandran S, Cassagnau P, Reiter G, Al Akhrass S. Tuning relaxation dynamics and mechanical properties of polymer films of identical thickness. Phys Rev E 2018; 97:032507. [PMID: 29776131 DOI: 10.1103/physreve.97.032507] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Indexed: 11/07/2022]
Abstract
Using dewetting as a characterization tool, we demonstrate that physical properties of thin polymer films can be regulated and tuned by employing variable processing conditions. For different molecular weights, the variable behavior of polystyrene films of identical thickness, prepared along systematically altered pathways, became predictable through a single parameter P, defined as the ratio of time required over time available for the equilibration of polymers. In particular, preparation-induced residual stresses, the corresponding relaxation times as well as the rupture probability of such films (of identical thickness) varied by orders of magnitude following scaling relations with P. Our experimental findings suggest that we can predictably enhance properties and hence maximize the performance of thin polymer films via appropriately chosen processing conditions.
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Affiliation(s)
- Marwa Kchaou
- Université Claude Bernard Lyon 1, Ingénierie des Matériaux Polymères (IMP - UMR CNRS 5223), 15 Boulevard Latarjet, 69622 Villeurbanne Cedex, France
| | - Pierre Alcouffe
- Université Claude Bernard Lyon 1, Ingénierie des Matériaux Polymères (IMP - UMR CNRS 5223), 15 Boulevard Latarjet, 69622 Villeurbanne Cedex, France
| | | | - Philippe Cassagnau
- Université Claude Bernard Lyon 1, Ingénierie des Matériaux Polymères (IMP - UMR CNRS 5223), 15 Boulevard Latarjet, 69622 Villeurbanne Cedex, France
| | - Günter Reiter
- Institute of Physics, University of Freiburg, 79104 Freiburg, Germany.,Freiburg Materials Research Center, University of Freiburg, 79104 Freiburg, Germany
| | - Samer Al Akhrass
- Université Claude Bernard Lyon 1, Ingénierie des Matériaux Polymères (IMP - UMR CNRS 5223), 15 Boulevard Latarjet, 69622 Villeurbanne Cedex, France
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9
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Chebil MS, Vignaud G, Bal JK, Beuvier T, Delorme N, Grohens Y, Gibaud A. Reversibility in glass transition behavior after erasing stress induced by spin coating process. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.06.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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10
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McGraw JD, Klos M, Bridet A, Hähl H, Paulus M, Castillo JM, Horsch M, Jacobs K. Influence of bidisperse self-assembled monolayer structure on the slip boundary condition of thin polymer films. J Chem Phys 2017; 146:203326. [DOI: 10.1063/1.4978676] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Joshua D. McGraw
- Soft Matter Physics Group, Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
- Département de Physique, Ecole Normale Supérieure/PSL Research University, CNRS, 24 Rue Lhomond, 75005 Paris, France
| | - Mischa Klos
- Soft Matter Physics Group, Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Antoine Bridet
- Soft Matter Physics Group, Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Hendrik Hähl
- Soft Matter Physics Group, Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Michael Paulus
- Fakultät Physik/DELTA, TU Dortmund, 44221 Dortmund, Germany
| | - Juan Manuel Castillo
- Laboratory of Engineering Thermodynamics, University of Kaiserslautern, Erwin-Schrödinger-Strasse 44, 67663 Kaiserslautern, Germany
| | - Martin Horsch
- Laboratory of Engineering Thermodynamics, University of Kaiserslautern, Erwin-Schrödinger-Strasse 44, 67663 Kaiserslautern, Germany
| | - Karin Jacobs
- Soft Matter Physics Group, Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
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11
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Zuo B, Liu Y, Liang Y, Kawaguchi D, Tanaka K, Wang X. Glass Transition Behavior in Thin Polymer Films Covered with a Surface Crystalline Layer. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02740] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Biao Zuo
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | - Yue Liu
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | - Yongfeng Liang
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | | | | | - Xinping Wang
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
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12
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Lee TH, Park SY, Walker B, Ko SJ, Heo J, Woo HY, Choi H, Kim JY. A universal processing additive for high-performance polymer solar cells. RSC Adv 2017. [DOI: 10.1039/c6ra27944a] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Diphenyl ether acts as a predominant processing additive regardless of the polymer crystallinity in bulk-heterojunction polymer solar cells.
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Affiliation(s)
- Tack Ho Lee
- Department of Energy Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Republic of Korea
| | - Song Yi Park
- Department of Energy Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Republic of Korea
| | - Bright Walker
- Department of Energy Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Republic of Korea
| | - Seo-Jin Ko
- Department of Energy Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Republic of Korea
| | - Jungwoo Heo
- Department of Energy Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Republic of Korea
| | - Han Young Woo
- Department of Chemistry
- Korea University
- Seoul 136-713
- Republic of Korea
| | - Hyosung Choi
- Department of Chemistry and Research Institute for Convergence of Basic Sciences
- Hanyang University
- Seoul 133-791
- Republic of Korea
| | - Jin Young Kim
- Department of Energy Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Republic of Korea
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13
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Chowdhury M, Sheng X, Ziebert F, Yang ACM, Sepe A, Steiner U, Reiter G. Intrinsic Stresses in Thin Glassy Polymer Films Revealed by Crack Formation. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01640] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Xiaoyuan Sheng
- Adolphe Merkle Institute, Chemin des
Verdiers, 1700 Fribourg, Switzerland
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Falko Ziebert
- Institut Charles
Sadron UPR22-CNRS, 67034 Strasbourg, Cedex 2, France
| | - Arnold C.-M. Yang
- Department
of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan
| | - Alessandro Sepe
- Adolphe Merkle Institute, Chemin des
Verdiers, 1700 Fribourg, Switzerland
| | - Ullrich Steiner
- Adolphe Merkle Institute, Chemin des
Verdiers, 1700 Fribourg, Switzerland
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14
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Fowler PD, Ruscher C, McGraw JD, Forrest JA, Dalnoki-Veress K. Controlling Marangoni-induced instabilities in spin-cast polymer films: How to prepare uniform films. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2016; 39:90. [PMID: 27681887 DOI: 10.1140/epje/i2016-16090-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 09/07/2016] [Indexed: 05/27/2023]
Abstract
In both research and industrial settings spincoating is extensively used to prepare highly uniform thin polymer films. However, under certain conditions, spincoating results in films with non-uniform surface morphologies. Although the spincoating process has been extensively studied, the origin of these morphologies is not fully understood and the formation of non-uniform spin-cast films remains a practical problem. Here we report on experiments demonstrating that the formation of surface instabilities during spincoating is dependent on temperature. Our results suggest that non-uniform spin-cast films form as a result of the Marangoni effect, which describes flow due to surface tension gradients. We find that both the wavelength and amplitude of the pattern increase with temperature. Finally, and most important from a practical viewpoint, the non-uniformities in the film thickness can be entirely avoided simply by lowering the spin coating temperature.
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Affiliation(s)
- Paul D Fowler
- Department of Physics & Astronomy, McMaster University, L8S 4M1, Hamilton, Ontario, Canada
| | - Céline Ruscher
- Department of Physics & Astronomy, McMaster University, L8S 4M1, Hamilton, Ontario, Canada
- Institut Charles Sadron, Université de Strasbourg, Strasbourg, France
| | - Joshua D McGraw
- Département de Physique, Ecole Normale Supérieure / PSL Research University, CNRS, 24 rue Lhomond, 75005, Paris, France
| | - James A Forrest
- Department of Physics & Astronomy, University of Waterloo, N2L 3G1, Waterloo, Ontario, Canada
| | - Kari Dalnoki-Veress
- Department of Physics & Astronomy, McMaster University, L8S 4M1, Hamilton, Ontario, Canada.
- Laboratoire de Physico-Chimie Théorique, UMR CNRS 7083 Gulliver, ESPCI ParisTech, PSL Research University, Paris, France.
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15
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Chandran S, Reiter G. Transient Cooperative Processes in Dewetting Polymer Melts. PHYSICAL REVIEW LETTERS 2016; 116:088301. [PMID: 26967445 DOI: 10.1103/physrevlett.116.088301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Indexed: 06/05/2023]
Abstract
We compare the high velocity dewetting behavior, at elevated temperatures, of atactic polystyrene (aPS) and isotactic polystyrene (iPS) films, with the zero shear bulk viscosity (η_{bulk}) of aPS being approximately ten times larger than iPS. As expected, for aPS the apparent viscosity of the films (η_{f}) derived from high-shear dewetting is less than η_{bulk}, displaying a shear thinning behavior. Surprisingly, for iPS films, η_{f} is always larger than η_{bulk}, even at about 50 °C above the melting point, with η_{f}/η_{bulk} following an Arrhenius behavior. The corresponding activation energy of ∼160±10 kJ/mol for iPS films suggests a cooperative motion of segments which are aligned and agglomerated by fast dewetting.
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Affiliation(s)
| | - Günter Reiter
- Institute of Physics, Albert Ludwig University of Freiburg, 79104 Freiburg, Germany
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16
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Al-Khayat O, Geraghty K, Shou K, Nelson A, Neto C. Chain Collapse and Interfacial Slip of Polystyrene Films in Good/Nonsolvent Vapor Mixtures. Macromolecules 2016. [DOI: 10.1021/acs.macromol.5b02253] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Omar Al-Khayat
- School
of Chemistry, and §School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Kieran Geraghty
- School
of Chemistry, and §School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Keyun Shou
- School
of Chemistry, and §School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Andrew Nelson
- Australian
Nuclear Science and Technology Organisation, Bragg Institute, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Chiara Neto
- School
of Chemistry, and §School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
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17
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Zuo B, He X, Wang Y, Xu J, Yang J, Wang X. Relationship between Segmental Relaxation of Polystyrene Films and Stick-Slip Behavior during Dynamic Wetting of Liquid Droplets on Their Surfaces. J Phys Chem B 2015; 119:12325-35. [PMID: 26305980 DOI: 10.1021/acs.jpcb.5b06078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel method was previously reported for detecting the glass transition of thin polystyrene (PS) films by correlating the relationships between the temperature-dependent viscoelasticity of the PS films and stick-slip behavior on their surfaces during dynamic wetting of liquid droplets. In the present study, the frequency dependence of the stick-slip behavior is investigated. The results show that the stick-slip behavior of liquid dynamic wetting on PS films is dependent on the contact line velocity, which is related to the deformation frequency of the PS surface during the moving liquid front. The stick-slip behavior was revealed to be determined by a dimensionless parameter (ξ), which is the ratio of the PS segmental relaxation time (τα) and the characteristic time (τc) for PS surface deformation near the droplet contact line. When ξ is close to 1 (τα ≈ τc), the Δθ (jumping angle), a scale of the stick-slip behavior, reaches a maximum. This correlation between Δθ and ξ demonstrates that the stick-slip behavior is related to the energy dissipation caused by the PS α-relaxation process, and the peak temperature (or frequency) in Δθ corresponds to the α-relaxation temperature (time) of the polymer. These results strongly demonstrate that the utilization of the stick-slip behavior is a creditable method, similar to dynamic viscoelastic measurement, for probing the glass transition and segmental relaxation of thin polymer films.
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Affiliation(s)
- Biao Zuo
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University , Hangzhou 310018, P. R. China
| | - Xumiao He
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University , Hangzhou 310018, P. R. China
| | - Yuping Wang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University , Hangzhou 310018, P. R. China
| | - Jianquan Xu
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University , Hangzhou 310018, P. R. China
| | - Juping Yang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University , Hangzhou 310018, P. R. China
| | - Xinping Wang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University , Hangzhou 310018, P. R. China
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18
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Solar M, Paul W. Dielectric α-relaxation of 1,4-polybutadiene confined between graphite walls : Molecular dynamics investigations through numerical simulations of polymer molecules relaxation. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2015; 38:123. [PMID: 25967943 DOI: 10.1140/epje/i2015-15037-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 03/11/2015] [Accepted: 03/11/2015] [Indexed: 06/04/2023]
Abstract
We present results of Molecular Dynamics (MD) simulations of a chemically realistic model of 1,4-polybutadiene confined by crystalline graphite walls. The simulations cover a large range of temperatures from T ≈ 2T g to T ≈ 1.15T g, where relevant time scales are accessible using such computational methods. We investigate the dielectric relaxation close to the walls in comparison to the one in the center of the film, and study the latter as a function of the film thickness from the walls. The segmental dynamics in the film is slowed down close to the walls, in comparison to the bulk. In addition to the α-process, the relaxation exhibits an additional long time decay, the so-called wall desorption process. We focus here on the α-process and find no significant shift of the dielectric T g as a function of layer thickness, in agreement with recent dielectric experiments. These findings can be correlated with the importance of the dihedral dynamics for all relaxation processes in polymers, which is unaltered except for the first nanometer next to the walls.
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Affiliation(s)
- M Solar
- Institut Charles Sadron (UPR22-CNRS), University of Strasbourg, 23 rue du Loess, BP 84047, F-67034, Strasbourg, France,
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19
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Lu XL, Mi YL. Glass transition behavior of spin-coated thin films of a hydrophilic polymer on supported substrates. CHINESE JOURNAL OF POLYMER SCIENCE 2015. [DOI: 10.1007/s10118-015-1612-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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20
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Benzaquen M, Fowler P, Jubin L, Salez T, Dalnoki-Veress K, Raphaël E. Approach to universal self-similar attractor for the levelling of thin liquid films. SOFT MATTER 2014; 10:8608-8614. [PMID: 25180467 DOI: 10.1039/c4sm01483a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We compare the capillary levelling of a random surface perturbation on a thin polystyrene film with a theoretical study on the two-dimensional capillary-driven thin film equation. Using atomic force microscopy, we follow the time evolution of samples prepared with different initial perturbations of the free surface. In particular, we show that the surface profiles present long term self-similarity, and furthermore, that they converge to a universal self-similar attractor that only depends on the volume of the perturbation, consistent with the theory. Finally, we look at the convergence time for the different samples and find very good agreement with the analytical predictions.
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Affiliation(s)
- Michael Benzaquen
- Laboratoire de Physico-Chimie Théorique, UMR CNRS 7083 Gulliver, ESPCI ParisTech, PSL Research University, France.
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21
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Tian H, Yang Y, Ding J, Liu W, Zuo B, Yang J, Wang X. Surface dynamics of poly(methyl methacrylate) films affected by the concentration of casting solutions. SOFT MATTER 2014; 10:6347-6356. [PMID: 25036734 DOI: 10.1039/c4sm00918e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The effect of the concentration of casting solutions on the surface dynamics of the corresponding spin-coated poly(methyl methacrylate) (PMMA) film was investigated by measuring the surface reorganization of fluorine tracer-labeled PMMA. The onset temperature of fluorinated PMMA chain end reorganization (T(onsetR)) was identified and is shown to depend on the PMMA concentration in the film-forming solution. It was found that the surface T(onsetR) and relaxation activation energy E(a) of the PMMA films prepared from 4.2 wt% PMMA cyclohexanone solution are 70 °C and 260 kJ mol(-1), respectively, which are higher than those of the PMMA films prepared from 0.8 wt% PMMA cyclohexanone solution (55 °C and 144 kJ mol(-1), respectively). The T(onsetR) and E(a) of PMMA films increased with increasing concentration of casting solutions within the range of 1.8 wt% to 4 wt%. The chain entanglement of PMMA chains is proposed to be the speculative origin for these observed depressed dynamics of poly(methyl methacrylate) chains on the films' surface prepared using casting solutions of various concentrations.
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Affiliation(s)
- Houkuan Tian
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of the Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
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22
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McGraw JD, Bäumchen O, Klos M, Haefner S, Lessel M, Backes S, Jacobs K. Nanofluidics of thin polymer films: linking the slip boundary condition at solid-liquid interfaces to macroscopic pattern formation and microscopic interfacial properties. Adv Colloid Interface Sci 2014; 210:13-20. [PMID: 24780402 DOI: 10.1016/j.cis.2014.03.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Revised: 03/28/2014] [Accepted: 03/28/2014] [Indexed: 10/25/2022]
Abstract
If a thin liquid film is not stable, different rupture mechanisms can be observed causing characteristic film morphologies: spinodal dewetting and dewetting by nucleation of holes. This rupturing entails liquid flow and opens new possibilities to study microscopic phenomena. Here we use this process of dewetting to gain insight on the slip boundary condition at the solid-liquid interface. Having established hydrodynamic models that allow for the determination of the slip length in a dewetting experiment based on nucleation, we move on to the quantification and molecular description of slip effects in various systems. For the late stage of the dewetting process involving the Rayleigh-Plateau instability, several distinct droplet patterns can be observed. We describe the importance of slip in determining what pattern may be found. In order to control the slip length, we use polymeric liquids on different hydrophobic coatings of silicon wafers. We find that subtle changes in the coating can lead to large changes in the slip length. Thus, we gain insight into the question of how the structure of the substrate affects the slip length.
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23
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Sheng X, Wintzenrieth F, Thomas KR, Steiner U. Intrinsic viscoelasticity in thin high-molecular-weight polymer films. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:062604. [PMID: 25019807 DOI: 10.1103/physreve.89.062604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Indexed: 06/03/2023]
Abstract
The rheology of 44-75-nm-thick polystyrene films were probed by destabilization in an electric field. The non-cross-linked films showed the hallmark of viscoelasiticy; they exhibited elastic behavior at high shear rates and viscous rheology at low shear rates for stationary applied fields. These results are interpreted in terms of surface adhesion of chain segments in contact with the substrate surface, which substantially reduces reptative molecular motion of nearly all chains within the film.
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Affiliation(s)
- Xiaoyuan Sheng
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | | | - Katherine R Thomas
- Max-Planck Institute for Dynamics and Self-Organization, Am Fassberg 17, 37077 Göttingen, Germany
| | - Ullrich Steiner
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
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24
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Myers JN, Zhang C, Chen C, Chen Z. Influence of casting solvent on phenyl ordering at the surface of spin cast polymer thin films. J Colloid Interface Sci 2014; 423:60-6. [DOI: 10.1016/j.jcis.2014.02.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/17/2014] [Accepted: 02/21/2014] [Indexed: 10/25/2022]
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25
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Backholm M, Benzaquen M, Salez T, Raphaël E, Dalnoki-Veress K. Capillary levelling of a cylindrical hole in a viscous film. SOFT MATTER 2014; 10:2550-2558. [PMID: 24647857 DOI: 10.1039/c3sm52940a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The capillary levelling of cylindrical holes in viscous polystyrene films was studied using atomic force microscopy as well as quantitative analytical scaling arguments based on thin film theory and self-similarity. The relaxation of the holes was shown to consist of two different time regimes: an early regime where opposing sides of the hole do not interact, and a late regime where the hole is filling up. For the latter, the self-similar asymptotic profile was derived analytically and shown to be in excellent agreement with experimental data. Finally, a binary system of two holes in close proximity was investigated where the individual holes fill up at early times and coalesce at longer times.
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Affiliation(s)
- Matilda Backholm
- Department of Physics & Astronomy and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada.
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26
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Entropy reduction phenomenon in the non-equilibrium state of freeze-dried polymethyl methacrylate samples. JOURNAL OF POLYMER RESEARCH 2014. [DOI: 10.1007/s10965-014-0392-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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27
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In-situ Observation of the Growth of Fibrous and Dendritic Crystals in Quasi-2-dimensional Poly(ethylene oxide) Ultrathin Films. Chin J Chem Eng 2014. [DOI: 10.1016/s1004-9541(14)60046-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Singh V, Lin PT, Patel N, Lin H, Li L, Zou Y, Deng F, Ni C, Hu J, Giammarco J, Soliani AP, Zdyrko B, Luzinov I, Novak S, Novak J, Wachtel P, Danto S, Musgraves JD, Richardson K, Kimerling LC, Agarwal AM. Mid-infrared materials and devices on a Si platform for optical sensing. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2014; 15:014603. [PMID: 27877641 PMCID: PMC5090602 DOI: 10.1088/1468-6996/15/1/014603] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 01/30/2014] [Accepted: 12/01/2013] [Indexed: 05/14/2023]
Abstract
In this article, we review our recent work on mid-infrared (mid-IR) photonic materials and devices fabricated on silicon for on-chip sensing applications. Pedestal waveguides based on silicon are demonstrated as broadband mid-IR sensors. Our low-loss mid-IR directional couplers demonstrated in SiN x waveguides are useful in differential sensing applications. Photonic crystal cavities and microdisk resonators based on chalcogenide glasses for high sensitivity are also demonstrated as effective mid-IR sensors. Polymer-based functionalization layers, to enhance the sensitivity and selectivity of our sensor devices, are also presented. We discuss the design of mid-IR chalcogenide waveguides integrated with polycrystalline PbTe detectors on a monolithic silicon platform for optical sensing, wherein the use of a low-index spacer layer enables the evanescent coupling of mid-IR light from the waveguides to the detector. Finally, we show the successful fabrication processing of our first prototype mid-IR waveguide-integrated detectors.
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Affiliation(s)
- Vivek Singh
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Pao Tai Lin
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Neil Patel
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hongtao Lin
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Lan Li
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Yi Zou
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Fei Deng
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Chaoying Ni
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Juejun Hu
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - James Giammarco
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Anna Paola Soliani
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Bogdan Zdyrko
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Igor Luzinov
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Spencer Novak
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Jackie Novak
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Peter Wachtel
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Sylvain Danto
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - J David Musgraves
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Kathleen Richardson
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
- College of Optics and Photonics, CREOL, University of Central Florida, Orlando, FL 32816, USA
| | - Lionel C Kimerling
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Anuradha M Agarwal
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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29
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Li L, Zhou D, Huang D, Xue G. Double Glass Transition Temperatures of Poly(methyl methacrylate) Confined in Alumina Nanotube Templates. Macromolecules 2013. [DOI: 10.1021/ma4020017] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Linling Li
- Department
of Polymer Science and Engineering, School of Chemistry and Chemical
Engineering, State Key Laboratory of Coordination Chemistry, Nanjing
National Laboratory of Microstructure, Nanjing University, Nanjing, 210093, P. R. China
| | - Dongshan Zhou
- Department
of Polymer Science and Engineering, School of Chemistry and Chemical
Engineering, State Key Laboratory of Coordination Chemistry, Nanjing
National Laboratory of Microstructure, Nanjing University, Nanjing, 210093, P. R. China
| | - Dinghai Huang
- Department
of Polymer Material Science and Engineering, School of Material Science
and Engineering, Tianjin University, Tianjin, 300072, P. R. China
| | - Gi Xue
- Department
of Polymer Science and Engineering, School of Chemistry and Chemical
Engineering, State Key Laboratory of Coordination Chemistry, Nanjing
National Laboratory of Microstructure, Nanjing University, Nanjing, 210093, P. R. China
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30
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Ediger MD, Forrest JA. Dynamics near Free Surfaces and the Glass Transition in Thin Polymer Films: A View to the Future. Macromolecules 2013. [DOI: 10.1021/ma4017696] [Citation(s) in RCA: 385] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. D. Ediger
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - J. A. Forrest
- Department
of Physics and Astronomy, University of Waterloo, 200 University
Avenue W., Waterloo, Ontario, Canada N2L 3G1
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31
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Napolitano S, Cangialosi D. Interfacial Free Volume and Vitrification: Reduction in Tg in Proximity of an Adsorbing Interface Explained by the Free Volume Holes Diffusion Model. Macromolecules 2013. [DOI: 10.1021/ma401368p] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Simone Napolitano
- Laboratory
of Polymer and Soft Matter Dynamics, Faculté des Sciences, Université Libre de Bruxelles, Boulevard du Triomphe, Bâtiment NO, Bruxelles 1050, Belgium
| | - Daniele Cangialosi
- Centro de Física de Materiales (CSIC-UPV/EHU), Paseo Manuel de Lardizabal
5, 20018 San Sebastián, Spain
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32
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Chen J, Xu J, Wang X, Zhou D, Sun P, Xue G. Thickness Dependence of Glass Transitions Measured by AC-Chip Calorimetry in Films with Controlled Interface. Macromolecules 2013. [DOI: 10.1021/ma401257y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jiao Chen
- Department of Polymer Science
and Engineering, School of Chemistry and Chemical Engineering, State
Key Laboratory of Co-ordination Chemistry, Nanjing National Laboratory
of Microstructures, Nanjing University,
Nanjing 210093, P. R. China
| | - Jie Xu
- Department of Polymer Science
and Engineering, School of Chemistry and Chemical Engineering, State
Key Laboratory of Co-ordination Chemistry, Nanjing National Laboratory
of Microstructures, Nanjing University,
Nanjing 210093, P. R. China
| | - Xiaoliang Wang
- Department of Polymer Science
and Engineering, School of Chemistry and Chemical Engineering, State
Key Laboratory of Co-ordination Chemistry, Nanjing National Laboratory
of Microstructures, Nanjing University,
Nanjing 210093, P. R. China
| | - Dongshan Zhou
- Department of Polymer Science
and Engineering, School of Chemistry and Chemical Engineering, State
Key Laboratory of Co-ordination Chemistry, Nanjing National Laboratory
of Microstructures, Nanjing University,
Nanjing 210093, P. R. China
| | - Pingchuan Sun
- Key Laboratory of Functional
Polymer Materials, Ministry of Education, College of Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Gi Xue
- Department of Polymer Science
and Engineering, School of Chemistry and Chemical Engineering, State
Key Laboratory of Co-ordination Chemistry, Nanjing National Laboratory
of Microstructures, Nanjing University,
Nanjing 210093, P. R. China
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33
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Benzaquen M, Salez T, Raphaël E. Intermediate asymptotics of the capillary-driven thin-film equation. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:82. [PMID: 23921450 DOI: 10.1140/epje/i2013-13082-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 06/10/2013] [Indexed: 05/28/2023]
Abstract
We present an analytical and numerical study of the two-dimensional capillary-driven thin-film equation. In particular, we focus on the intermediate asymptotics of its solutions. Linearising the equation enables us to derive the associated Green's function and therefore obtain a complete set of solutions. Moreover, we show that the rescaled solution for any summable initial profile uniformly converges in time towards a universal self-similar attractor that is precisely the rescaled Green's function. Finally, a numerical study on compact-support initial profiles enables us to conjecture the extension of our results to the nonlinear equation.
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Affiliation(s)
- Michael Benzaquen
- Laboratoire de Physico-Chimie Théorique, UMR CNRS Gulliver 7083, ESPCI, Paris, France
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34
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Lin Y, Tan Y, Qiu B, Cheng J, Wang W, Shangguan Y, Zheng Q. Casting solvent effects on molecular dynamics of weak dynamic asymmetry polymer blend films via broadband dielectric spectroscopy. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2013.03.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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35
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Lin Y, Tan Y, Qiu B, Shangguan Y, Harkin-Jones E, Zheng Q. Influence of Annealing on Chain Entanglement and Molecular Dynamics in Weak Dynamic Asymmetry Polymer Blends. J Phys Chem B 2013; 117:697-705. [DOI: 10.1021/jp3098507] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yu Lin
- MOE Key Laboratory of Macromolecular
Synthesis and Functionalization, Department of Polymer Science and
Engineering, Zhejiang University, Hangzhou
310027, People’s Republic of China
| | - Yeqiang Tan
- MOE Key Laboratory of Macromolecular
Synthesis and Functionalization, Department of Polymer Science and
Engineering, Zhejiang University, Hangzhou
310027, People’s Republic of China
| | - Biwei Qiu
- MOE Key Laboratory of Macromolecular
Synthesis and Functionalization, Department of Polymer Science and
Engineering, Zhejiang University, Hangzhou
310027, People’s Republic of China
| | - Yonggang Shangguan
- MOE Key Laboratory of Macromolecular
Synthesis and Functionalization, Department of Polymer Science and
Engineering, Zhejiang University, Hangzhou
310027, People’s Republic of China
| | - Eileen Harkin-Jones
- Polymers Research Cluster, School
of Mechanical and Aerospace Engineering, Queen’s University Belfast, Belfast BT9 5AH, United Kingdom
| | - Qiang Zheng
- MOE Key Laboratory of Macromolecular
Synthesis and Functionalization, Department of Polymer Science and
Engineering, Zhejiang University, Hangzhou
310027, People’s Republic of China
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36
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McGraw JD, Fowler PD, Ferrari ML, Dalnoki-Veress K. Relaxation of non-equilibrium entanglement networks in thin polymer films. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:7. [PMID: 23355094 DOI: 10.1140/epje/i2013-13007-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 01/11/2013] [Indexed: 06/01/2023]
Abstract
It is known that polymer films, prepared by spin coating, inherit non-equilibrium configurations which can affect macroscopic film properties. Here we present the results of crazing experiments that support this claim; our measurements indicate that the as-cast chain configurations are strongly stretched as compared to equilibrium Gaussian configurations. The results of our experiments also demonstrate that the entanglement network equilibrates on a time scale comparable to one reptation time. Having established that films can be prepared with an equilibrium entanglement network, we proceed by confining polymers to films in which the thickness is comparable to the molecular size. By stacking two such films, a bilayer is created with a buried entropic interface. Such an interface has no enthalpic cost, only an entropic penalty associated with the restricted configurations of molecules that cannot cross the mid-plane of the bilayer. In the melt, the entropic interface heals as chains from the two layers mix and entangle with one another; crazing measurements allow us to probe the dynamics of two films becoming one. Healing of the entropic interface is found to take less than one bulk reptation time.
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Affiliation(s)
- Joshua D McGraw
- Department of Physics & Astronomy and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada
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37
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Salez T, McGraw JD, Cormier SL, Bäumchen O, Dalnoki-Veress K, Raphaël E. Numerical solutions of thin-film equations for polymer flows. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2012; 35:114. [PMID: 23138477 DOI: 10.1140/epje/i2012-12114-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 10/09/2012] [Accepted: 10/10/2012] [Indexed: 06/01/2023]
Abstract
We report on the numerical implementation of thin-film equations that describe the capillary-driven evolution of viscous films, in two-dimensional configurations. After recalling the general forms and features of these equations, we focus on two particular cases inspired by experiments: the leveling of a step at the free surface of a polymer film, and the leveling of a polymer droplet over an identical film. In each case, we first discuss the long-term self-similar regime reached by the numerical solution before comparing it to the experimental profile. The agreement between theory and experiment is excellent, thus providing a versatile probe for nanorheology of viscous liquids in thin-film geometries.
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Affiliation(s)
- Thomas Salez
- Laboratoire de Physico-Chimie Théorique, UMR CNRS Gulliver, ESPCI, Paris, France.
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38
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Napolitano S, Rotella C, Wübbenhorst M. Can Thickness and Interfacial Interactions Univocally Determine the Behavior of Polymers Confined at the Nanoscale? ACS Macro Lett 2012; 1:1189-1193. [PMID: 35607193 DOI: 10.1021/mz300432d] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The behavior of polymers confined in ultrathin films (thickness < 200 nm) can sensitively differ from that observed in macroscopic samples. Based on the simple arguments of finite size and interfacial effects, film thickness, and surface interactions should be sufficient to univocally determine the deviation from bulk behavior. However, recent models suggest that a third key parameter, namely, the interfacial free volume, should also be considered. We describe a novel methodology that quantifies the volume available for structural relaxation at the interface between a thin polymer layer and its supporting substrate. Experiments performed at different annealing conditions verified that the shift in glass transition temperature, measured in thin films upon confinement, is proportional to the degree of adsorption and, thus, to the interfacial free volume.
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Affiliation(s)
- Simone Napolitano
- Laboratory
of Polymer
and Soft Matter Dynamics, Université Libre de Bruxelles, Boulevard du Triomphe, Bruxelles
1050, Belgium
| | - Cinzia Rotella
- Department of Physics
and Astronomy, Katholieke Universiteit Leuven, Celestijnenlaan 200D, Leuven, 3001, Belgium
| | - Michael Wübbenhorst
- Department of Physics
and Astronomy, Katholieke Universiteit Leuven, Celestijnenlaan 200D, Leuven, 3001, Belgium
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39
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Chowdhury M, Freyberg P, Ziebert F, Yang ACM, Steiner U, Reiter G. Segmental relaxations have macroscopic consequences in glassy polymer films. PHYSICAL REVIEW LETTERS 2012; 109:136102. [PMID: 23030107 DOI: 10.1103/physrevlett.109.136102] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 08/01/2012] [Indexed: 06/01/2023]
Abstract
We have investigated the consequences of physical aging in thin spin-coated glassy polystyrene films through detailed dewetting studies. A simultaneous and equally fast exponential decay of dewetting velocity, width, and height of the rim with aging time was observed, which is related to a reduction of residual stresses within such films. The temperature dependence of these decay times followed an Arrhenius behavior, yielding an activation energy of 70±6 kJ/mol, on the same order of magnitude as values for the β-relaxation of polystyrene and for relaxations of surface topographical features. Our results suggest that rearrangements at the level of chain segments are sufficient to partially relax frozen-in out-of-equilibrium local chain conformations, i.e., the cause of residual stresses, and they might also be responsible for macroscopic relaxations at polymer surfaces.
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Affiliation(s)
- Mithun Chowdhury
- Physikalisches Institut, Albert-Ludwigs-Universität, 79104 Freiburg, Germany.
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40
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McGraw JD, Salez T, Bäumchen O, Raphaël E, Dalnoki-Veress K. Self-similarity and energy dissipation in stepped polymer films. PHYSICAL REVIEW LETTERS 2012; 109:128303. [PMID: 23005996 DOI: 10.1103/physrevlett.109.128303] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/04/2012] [Indexed: 06/01/2023]
Abstract
The surface of a thin liquid film with a nonconstant curvature is unstable, as the Laplace pressure drives a flow mediated by viscosity. We present the results of experiments on one of the simplest variable curvature surfaces: a thin polymer film with a step. Height profiles are measured as a function of time for a variety of molecular weights. The evolution of the profiles is shown to be self-similar. This self-similarity offers a precise measurement of the capillary velocity by comparison with numerical solutions of the thin film equation. We also derive a master expression for the time dependence of the excess free energy as a function of the material properties and film geometry. The experiment and theory are in excellent agreement and indicate the effectiveness of stepped polymer films to elucidate nanoscale rheological properties.
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Affiliation(s)
- Joshua D McGraw
- Department of Physics and Astronomy, McMaster University, Hamilton, Canada
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41
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Bäumchen O, McGraw JD, Forrest JA, Dalnoki-Veress K. Reduced glass transition temperatures in thin polymer films: surface effect or artifact? PHYSICAL REVIEW LETTERS 2012; 109:055701. [PMID: 23006187 DOI: 10.1103/physrevlett.109.055701] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Indexed: 06/01/2023]
Abstract
We have examined the direct effect of manipulating the number of free surfaces on the measured glass transition temperature T(g) of thin polystyrene films. Thin films in the range 35 nm < h < 114 nm with molecular weights of 592 kg/mol and 1144 kg/mol were studied. Ellipsometry was used to determine the temperature dependence of the thickness and refractive index of freestanding films. By noting the change in slope in each of these quantities, a T(g) value can be assigned in quantitative agreement with previously reported results. For thin freestanding films this value is reduced from that of the bulk. The exact same films are then transferred to a Si substrate and the T(g) of the resulting supported film was determined. The T(g) values of the now supported films are the same as the bulk value and the same as previous reports of similar supported films. These experiments unambiguously show that free interfaces are the dominant cause of the T(g) reductions for the film thicknesses studied.
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Affiliation(s)
- O Bäumchen
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada
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42
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Efremov MY, Kiyanova AV, Last J, Soofi SS, Thode C, Nealey PF. Glass transition in thin supported polystyrene films probed by temperature-modulated ellipsometry in vacuum. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:021501. [PMID: 23005763 DOI: 10.1103/physreve.86.021501] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Indexed: 06/01/2023]
Abstract
Glass transition in thin (1-200 nm thick) spin-cast polystyrene films on silicon surfaces is probed by ellipsometry in a controlled vacuum environment. A temperature-modulated modification of the method is used alongside a traditional linear temperature scan. A clear glass transition is detected in films with thicknesses as low as 1-2 nm. The glass transition temperature (T(g)) shows no substantial dependence on thickness for coatings greater than 20 nm. Thinner films demonstrate moderate T(g) depression achieving 18 K for thicknesses 4-7 nm. Less than 4 nm thick samples are excluded from the T(g) comparison due to significant thickness nonuniformity (surface roughness). The transition in 10-20 nm thick films demonstrates excessive broadening. For some samples, the broadened transition is clearly resolved into two separate transitions. The thickness dependence of the glass transition can be well described by a simple 2-layer model. It is also shown that T(g) depression in 5 nm thick films is not sensitive to a wide range of experimental factors including molecular weight characteristics of the polymer, specifications of solvent used for spin casting, substrate composition, and pretreatment of the substrate surface.
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Affiliation(s)
- Mikhail Yu Efremov
- Department of Chemical and Biological Engineering and Center for Nanotechnology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
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43
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Teng C, Gao Y, Wang X, Jiang W, Zhang C, Wang R, Zhou D, Xue G. Reentanglement Kinetics of Freeze-Dried Polymers above the Glass Transition Temperature. Macromolecules 2012. [DOI: 10.1021/ma300885w] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chao Teng
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Yun Gao
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Xiaoliang Wang
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Wei Jiang
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Chen Zhang
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Rong Wang
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Dongshan Zhou
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Gi Xue
- Department of Polymer Science and Engineering, School
of Chemistry and Chemical Engineering, State Key Laboratory of Co-ordination
Chemistry, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
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44
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Clough A, Chowdhury M, Jahanshahi K, Reiter G, Tsui OKC. Swelling with a Near-Θ Solvent as a Means to Modify the Properties of Polymer Thin Films. Macromolecules 2012. [DOI: 10.1021/ma301122k] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrew Clough
- Department of Physics, Boston University, Boston, Massachusetts 02215, United
States
| | - Mithun Chowdhury
- Albert-Ludwigs-Universität Physikalisches Institut, D-79104, Freiburg, Germany
| | - Kaiwan Jahanshahi
- Albert-Ludwigs-Universität Physikalisches Institut, D-79104, Freiburg, Germany
| | - Günter Reiter
- Albert-Ludwigs-Universität Physikalisches Institut, D-79104, Freiburg, Germany
- Freiburg Institute for Advanced
Studies, Albert-Ludwigs-Universität, D-79104, Freiburg, Germany
| | - Ophelia K. C. Tsui
- Department of Physics, Boston University, Boston, Massachusetts 02215, United
States
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45
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Gray LAG, Yoon SW, Pahner WA, Davidheiser JE, Roth CB. Importance of Quench Conditions on the Subsequent Physical Aging Rate of Glassy Polymer Films. Macromolecules 2012. [DOI: 10.1021/ma202493n] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laura A. G. Gray
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
| | - Suk W. Yoon
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
| | - William A. Pahner
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
| | | | - Connie B. Roth
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
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46
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Li RN, Clough A, Yang Z, Tsui OKC. Equilibration of Polymer Films Cast from Solutions with Different Solvent Qualities. Macromolecules 2012. [DOI: 10.1021/ma202612q] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ranxing Nancy Li
- Department of Physics, Boston University, Boston, Massachusetts 02215, United
States
| | - Andrew Clough
- Department of Physics, Boston University, Boston, Massachusetts 02215, United
States
| | - Zhaohui Yang
- Department of Physics, Boston University, Boston, Massachusetts 02215, United
States
| | - Ophelia K. C. Tsui
- Department of Physics, Boston University, Boston, Massachusetts 02215, United
States
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47
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Probing Properties of Polymers in Thin Films Via Dewetting. GLASS TRANSITION, DYNAMICS AND HETEROGENEITY OF POLYMER THIN FILMS 2012. [DOI: 10.1007/12_2012_174] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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48
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Siretanu I, Chapel JP, Drummond C. Substrate Remote Control of Polymer Film Surface Mobility. Macromolecules 2011. [DOI: 10.1021/ma202187s] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Igor Siretanu
- Centre de Recherche Paul Pascal,
UPR8641, CNRS, Université de Bordeaux, Avenue Schweitzer, 33600 Pessac Cedex, France
- Laboratoire de Chimie des Polymères
Organiques, CNRS, Université Bordeaux 1, 33607 Pessac Cedex, France
| | - Jean Paul Chapel
- Centre de Recherche Paul Pascal,
UPR8641, CNRS, Université de Bordeaux, Avenue Schweitzer, 33600 Pessac Cedex, France
| | - Carlos Drummond
- Centre de Recherche Paul Pascal,
UPR8641, CNRS, Université de Bordeaux, Avenue Schweitzer, 33600 Pessac Cedex, France
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49
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Yang Z, Clough A, Lam CH, Tsui OKC. Glass Transition Dynamics and Surface Mobility of Entangled Polystyrene Films at Equilibrium. Macromolecules 2011. [DOI: 10.1021/ma201675z] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zhaohui Yang
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
| | - Andrew Clough
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
| | - Chi-Hang Lam
- Department of Applied Physics, Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - Ophelia K. C. Tsui
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
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50
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Giammarco J, Zdyrko B, Petit L, Musgraves JD, Hu J, Agarwal A, Kimerling L, Richardson K, Luzinov I. Towards universal enrichment nanocoating for IR-ATR waveguides. Chem Commun (Camb) 2011; 47:9104-6. [PMID: 21734984 DOI: 10.1039/c1cc12780b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polymer multilayered nanocoating capable of concentrating various chemical substances at IR-ATR waveguide surfaces is described. The coating affinity to an analyte played a pivotal role in sensitivity enhancement of the IR-ATR measurements, since the unmodified waveguide did not show any analyte detection.
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Affiliation(s)
- James Giammarco
- School of Materials Science and Engineering and the Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, SC 29634, USA
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