1
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Cheng S, Kogut D, Zheng J, Patil S, Yang F, Lu W. Dynamics of polylactic acid under ultrafine nanoconfinement: The collective interface effect and the spatial gradient. J Chem Phys 2024; 160:114904. [PMID: 38506298 DOI: 10.1063/5.0189762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/16/2024] [Indexed: 03/21/2024] Open
Abstract
Polymers under nanoconfinement can exhibit large alterations in dynamics from their bulk values due to an interface effect. However, understanding the interface effect remains a challenge, especially in the ultrafine nanoconfinement region. In this work, we prepare new geometries with ultrafine nanoconfinement ∼10nm through controlled distributions of the crystalline phases and the amorphous phases of a model semi-crystalline polymer, i.e., the polylactic acid. The broadband dielectric spectroscopy measurements show that ultrafine nanoconfinement leads to a large elevation in the glass transition temperature and a strong increment in the polymer fragility index. Moreover, new relaxation time profile analyses demonstrate a spatial gradient that can be well described by either a single-exponential decay or a double-exponential decay functional form near the middle of the film with a collective interface effect. However, the dynamics at the 1-2 nm vicinity of the interface exhibit a power-law decay that is different from the single-exponential decay or double-exponential decay functional forms as predicted by theories. Thus, these results call for further investigations of the interface effect on polymer dynamics, especially for interfaces with perturbed chain packing.
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Affiliation(s)
- Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - David Kogut
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Juncheng Zheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Shalin Patil
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Fuming Yang
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan 48824, USA
| | - Weiyi Lu
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan 48824, USA
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2
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Nobori H, Fujimoto D, Yoshioka J, Fukao K, Konishi T, Taguchi K. Phase transitions and dynamics in ionic liquid crystals confined in nanopores. J Chem Phys 2024; 160:044902. [PMID: 38258924 DOI: 10.1063/5.0185093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 01/01/2024] [Indexed: 01/24/2024] Open
Abstract
We investigate the phase-transition behavior of ionic liquid crystals, namely 1-methyl-3-alkylimidazolium tetrafluoroborate, [Cnmim]BF4, confined in cylindrical nanopores using differential scanning calorimetry, x-ray scattering, and dielectric relaxation spectroscopy. Here, n is the number of carbon atoms in the alkyl part of this ionic liquid crystal. For n = 10 and 12, the isotropic liquid phase changes to the smectic phase and then to a metastable phase for the cooling process. During the subsequent heating process, the metastable phase changes to the isotropic phase via crystalline phases. The transition temperatures for this ionic liquid crystal confined in nanopores decrease linearly with the increase in the inverse pore diameter, except for the transitions between the smectic and isotropic phases. In the metastable phase, the relaxation rate of the α-process shows the Vogel-Fulcher-Tammann type of temperature dependence for some temperature ranges. The glass transition temperature evaluated from the dynamics of the α-process decreases with the decrease in the pore diameter and increases with the increase in the carbon number n. The effect of confinement on the chain dynamics can clearly be observed for this ionic liquid crystal. For n = 10, the melting temperature of the crystalline phase is slightly higher than that of the smectic phase for the bulk, while, in the nanopores, the melting temperature of the smectic phase is higher than that of the crystalline phase. This suggests that the smectic phase can be thermodynamically stable, thanks to the confinement effect.
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Affiliation(s)
- Hiroki Nobori
- Department of Physics, Ritsumeikan University, Noji-Higashi 1-1-1, Kusatsu 525-8577, Japan
| | - Daisuke Fujimoto
- Department of Physics, Ritsumeikan University, Noji-Higashi 1-1-1, Kusatsu 525-8577, Japan
| | - Jun Yoshioka
- Department of Physics, Ritsumeikan University, Noji-Higashi 1-1-1, Kusatsu 525-8577, Japan
| | - Koji Fukao
- Department of Physics, Ritsumeikan University, Noji-Higashi 1-1-1, Kusatsu 525-8577, Japan
| | - Takashi Konishi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Ken Taguchi
- Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
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3
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Ghanekarade A, Simmons DS. Glass formation and dynamics of model polymer films with one versus two active interfaces. SOFT MATTER 2023; 19:8413-8422. [PMID: 37877245 DOI: 10.1039/d3sm00719g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Polymers and other glass-forming liquids can exhibit profound alterations in dynamics in the nanoscale vicinity of interfaces, over a range appreciably exceeding that of typical interfacial thermodynamic gradients. The understanding of these dynamical gradients is particularly complicated in systems with internal or external nanoscale dimensions, where a gradient nucleated at one interface can impinge on a second, potentially distinct, interface. To better understand the interactions that govern system dynamics and glass formation in these cases, here we simulate the baseline case of a glass-forming polymer film, over a wide range of thickness, supported on a dynamically neutral substrate that has little effect on nearby dynamics. We compare these results to our prior simulations of freestanding films. Results indicate that dynamical gradients in our simulated systems, as measured based upon translational relaxation, are simply truncated when they impinge on a secondary surface that is locally dynamically neutral. Altered film behavior can be described almost entirely by gradient effects down to the thinnest films probed, with no evidence for finite-size effects sometimes posited to play a role in these systems. Finally, our simulations predict that linear gradient overlap effects in the presence of symmetric dynamically active interfaces yield a non-monotonic variation of the whole free standing film stretching exponent (relaxation time distribution breadth). The maximum relaxation time distribution breadth in simulation is found at a film thickness of 4-5 times the interfacial gradient range. Observation of this maximum in experiment would provide an important validation that the gradient behavior observed in simulation persists to experimental timescales. If validated, observation of this maximum would potentially also enable determination of the dynamic gradient range from experimental mean-film measurements of film dynamics.
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Affiliation(s)
- Asieh Ghanekarade
- Department of Chemical, Biological, and Materials Engineering, The University of South Florida, Tampa, Florida, USA.
| | - David S Simmons
- Department of Chemical, Biological, and Materials Engineering, The University of South Florida, Tampa, Florida, USA.
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4
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Li A, Sheng Y, Cui H, Wang M, Wu L, Song Y, Yang R, Li X, Huang H. Discovery and mechanism-guided engineering of BHET hydrolases for improved PET recycling and upcycling. Nat Commun 2023; 14:4169. [PMID: 37443360 PMCID: PMC10344914 DOI: 10.1038/s41467-023-39929-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023] Open
Abstract
Although considerable research achievements have been made to address the plastic crisis using enzymes, their applications are limited due to incomplete degradation and low efficiency. Herein, we report the identification and subsequent engineering of BHETases, which have the potential to improve the efficiency of PET recycling and upcycling. Two BHETases (ChryBHETase and BsEst) are identified from the environment via enzyme mining. Subsequently, mechanism-guided barrier engineering is employed to yield two robust and thermostable ΔBHETases with up to 3.5-fold enhanced kcat/KM than wild-type, followed by atomic resolution understanding. Coupling ΔBHETase into a two-enzyme system overcomes the challenge of heterogeneous product formation and results in up to 7.0-fold improved TPA production than seven state-of-the-art PET hydrolases, under the conditions used here. Finally, we employ a ΔBHETase-joined tandem chemical-enzymatic approach to valorize 21 commercial post-consumed plastics into virgin PET and an example chemical (p-phthaloyl chloride) for achieving the closed-loop PET recycling and open-loop PET upcycling.
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Affiliation(s)
- Anni Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Yijie Sheng
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Haiyang Cui
- RWTH Aachen University, Templergraben 55, Aachen, 52062, Germany
- University of Illinois at Urbana-Champaign, Carl R. Woese Institute for Genomic Biology, 1206 West Gregory Drive, Urbana, IL, 61801, USA
| | - Minghui Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Luxuan Wu
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Yibo Song
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Rongrong Yang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Xiujuan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China.
| | - He Huang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China.
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5
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Tannoury L, Solar M, Paul W. Structure and dynamics of a 1,4-polybutadiene melt in an alumina nanopore: A molecular dynamics simulation. J Chem Phys 2022; 157:124901. [DOI: 10.1063/5.0105313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present results of Molecular Dynamics simulations of a chemically realistic model of 1,4-polybutadiene (PBD)confined in a cylindrical alumina nanopore of diameter 10 nm. The simulations are done at three different temperaturesabove the glass transition temperature T g . We investigate the density layering across the nanopore as well as theorientational ordering in the polymer melt, brought about by the confinement, on both the segmental and chain scales.For the chain scale ordering, the magnitude and orientation of the axes of the gyration tensor ellipsoid of single chainsare studied and are found to prefer to align parallel to the pore axis. Even though double bonds near the wall arepreferentially oriented along the pore walls, studying the nematic order parameter indicates that there is no nematicordering at the melt-wall interface. As for the dynamics in the melt, we focus here on the mean-square-displacement ofthe monomers for several layers across the nanopore as well as the movement of the chain center of mass which bothdisplay a slowing down of the dynamics in the layer at the wall. We also show the strong adsorption of the monomersto the pore wall at lower temperatures.
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Affiliation(s)
- Lama Tannoury
- Institute of Physics, Martin Luther University Halle Wittenberg, Germany
| | - Mathieu Solar
- Institut f. Physik, Institut National des Sciences Appliques, France
| | - Wolfgang Paul
- Institut f. Physik, Martin-Luther-Universität Halle-Wittenberg, Germany
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6
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Chat K, Tu W, Beena Unni A, Adrjanowicz K. Influence of Tacticity on the Glass-Transition Dynamics of Poly(methyl methacrylate) (PMMA) under Elevated Pressure and Geometrical Nanoconfinement. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01341] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Katarzyna Chat
- Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Wenkang Tu
- Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Aparna Beena Unni
- Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Karolina Adrjanowicz
- Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
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7
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Winkler R, Beena Unni A, Tu W, Chat K, Adrjanowicz K. On the Segmental Dynamics and the Glass Transition Behavior of Poly(2-vinylpyridine) in One- and Two-Dimensional Nanometric Confinement. J Phys Chem B 2021; 125:5991-6003. [PMID: 34048244 PMCID: PMC8279553 DOI: 10.1021/acs.jpcb.1c01245] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/13/2021] [Indexed: 11/30/2022]
Abstract
Geometric nanoconfinement, in one and two dimensions, has a fundamental influence on the segmental dynamics of polymer glass-formers and can be markedly different from that observed in the bulk state. In this work, with the use of dielectric spectroscopy, we have investigated the glass transition behavior of poly(2-vinylpyridine) (P2VP) confined within alumina nanopores and prepared as a thin film supported on a silicon substrate. P2VP is known to exhibit strong, attractive interactions with confining surfaces due to the ability to form hydrogen bonds. Obtained results show no changes in the temperature evolution of the α-relaxation time in nanopores down to 20 nm size and 24 nm thin film. There is also no evidence of an out-of-equilibrium behavior observed for other glass-forming systems confined at the nanoscale. Nevertheless, in both cases, the confinement effect is seen as a substantial broadening of the α-relaxation time distribution. We discussed the results in terms of the importance of the interfacial energy between the polymer and various substrates, the sensitivity of the glass-transition temperature to density fluctuations, and the density scaling concept.
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Affiliation(s)
- Roksana Winkler
- Institute
of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian
Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Aparna Beena Unni
- Institute
of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian
Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Wenkang Tu
- Institute
of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian
Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Katarzyna Chat
- Institute
of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian
Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Karolina Adrjanowicz
- Institute
of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
- Silesian
Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
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8
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Experimental evidence on the effect of substrate roughness on segmental dynamics of confined polymer films. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122501] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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9
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Popov I, Carroll B, Bocharova V, Genix AC, Cheng S, Khamzin A, Kisliuk A, Sokolov AP. Strong Reduction in Amplitude of the Interfacial Segmental Dynamics in Polymer Nanocomposites. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00496] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Ivan Popov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Bobby Carroll
- Department of Physics, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Vera Bocharova
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Anne-Caroline Genix
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, Montpellier F-34095, France
| | - Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lancing, Michigan 48824, United States
| | - Airat Khamzin
- Institute of Physics, Kazan Federal University, Kremlevskaya Str. 18, Kazan, Tatarstan 420008, Russia
| | - Alexander Kisliuk
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Alexei P. Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
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10
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Maithani S, Maity A, Pradhan M. A Prototype Evanescent Wave-Coupled Cavity Ring-down Spectrometer for Probing Real-Time Aggregation Kinetics of Gold and Silver Nanoparticles. Anal Chem 2020; 92:3998-4005. [PMID: 32008320 DOI: 10.1021/acs.analchem.9b05521] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report on the development of a simple, linear optical cavity-based system combining evanescent wave (EW) with high-sensitive cavity ring-down spectroscopy (CRDS) technique using a diode laser at 644 nm and a right-angled prism for evanescent field generation on prism surface. We characterized the setup in detail and achieved an optimum ring-down time of 159.4 ns and a minimum absorption coefficient of αmin = 1.67 × 10-6 cm-1. We utilized this setup to investigate the salt-induced aggregation kinetics of gold (Au) and silver (Ag) nanoparticles (NPs) at the prism interface with high-sensitivity. We evaluated the extinction rates on the surface due to Au and Ag NPs aggregation and examined the variations due to their respective concentrations. To demonstrate the applicability of the developed EW-CRDS prototype setup to different molecular systems, we investigated the urease-bound aggregation kinetics of the Au and Ag NPs which has not been explored earlier by this linear cavity geometry. We finally illustrated the aggregation dynamics through surface imaging, thus demonstrating an alternative analytical approach to monitor interfacial phenomena using EW-CRDS technique.
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Affiliation(s)
- Sanchi Maithani
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India
| | - Abhijit Maity
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India
| | - Manik Pradhan
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India.,Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India
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11
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Studying tautomerism in an important pharmaceutical glibenclamide confined in the thin nanometric layers. Colloids Surf B Biointerfaces 2019; 182:110319. [PMID: 31301581 DOI: 10.1016/j.colsurfb.2019.06.049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 06/20/2019] [Accepted: 06/21/2019] [Indexed: 11/24/2022]
Abstract
The uniform thin films with variable thicknesses (d = 49, 120, 220 nm) of active pharmaceutical ingredient (API) glibenclamide (GCM) was spin-coated and investigated using broadband dielectric, grazing incident FTIR spectroscopies, atomic force microscopy, and ellipsometry. Data analysis revealed that nanoconfined systems consist of a mixture of amide and imidic acid forms of this pharmaceutical, wherein the ratios of both tautomeric forms in the thin films were different with respect to the molten supercooled bulk system. Moreover, changes in the populations of glibenclamide tautomers, i.e. higher amide to imides ratio in the spatially restricted API with respect to the bulk sample, had a strong impact on the character of the proton transfer reaction. In this context, the kinetic curves constructed on the base of infrared data for the bulk system follow the sigmoidal shape, characteristic for the autocatalytic reaction, while results obtained for the confined samples provide exponential character and indicate first-order transformation. This allows hypothesizing that the autocatalytic nature of the tautomerism in the bulk sample is most likely related to the formation of the amide tautomers which further catalyze the progress of imide-amide transformation. Our results are the first studies showing that the change in the thickness of the film may affect the properties and isomerization kinetics in a pharmaceutical systems. Finally, our data open a new perspective for developing new drug delivery systems.
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12
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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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13
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Sharma RP, Dong BX, Green PF. Role of Thickness Confinement on Relaxations of the Fast Component in a Miscible A/B Blend. Macromolecules 2018. [DOI: 10.1021/acs.macromol.7b02152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - Peter F. Green
- National Renewable
Energy Laboratory, Golden, Colorado 80401, United States
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14
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Russell TP, Chai Y. 50th Anniversary Perspective: Putting the Squeeze on Polymers: A Perspective on Polymer Thin Films and Interfaces. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00418] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Thomas P. Russell
- Polymer
Science and Engineering Department, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Materials
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
- Beijing
Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yu Chai
- Materials
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
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15
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Merling WL, Mileski JB, Douglas JF, Simmons DS. The Glass Transition of a Single Macromolecule. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01461] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Weston L. Merling
- Department
of Polymer Engineering, The University of Akron, 250 South Forge
St., Akron, Ohio 44325-0301, United States
| | - Johnathon B. Mileski
- Department
of Polymer Engineering, The University of Akron, 250 South Forge
St., Akron, Ohio 44325-0301, United States
| | - Jack F. Douglas
- Materials
Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - David S. Simmons
- Department
of Polymer Engineering, The University of Akron, 250 South Forge
St., Akron, Ohio 44325-0301, United States
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16
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Zuo B, Tian H, Liang Y, Xu H, Zhang W, Zhang L, Wang X. Probing the rheological properties of supported thin polystyrene films by investigating the growth dynamics of wetting ridges. SOFT MATTER 2016; 12:6120-6131. [PMID: 27355155 DOI: 10.1039/c6sm00881j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Despite its importance in the processing of nanomaterials, the rheological behavior of thin polymer films is poorly understood, partly due to the inherent measurement challenges. Herein, we have developed a facile method for investigating the rheological behavior of supported thin polymeric films by monitoring the growth of the "wetting ridge"-a microscopic protrusion on the film surface due to the capillary forces exerted by a drop of ionic liquid placed on the film surface. It was found that the growth dynamics of the wetting ridge and the behavior of polystyrene rheology are directly linked. Important rheological properties, such as the flow temperature (Tf), viscosity (η), and terminal relaxation time (τ0) of thin polystyrene films, can be derived by studying the development of the height of the wetting ridge with time and the sample temperature. Rheological studies using the proposed approach for supported thin polystyrene (PS) films with thickness down to 20 nm demonstrate that the PS thin film exhibits facilitated flow, with reduced viscosity and lowered viscous temperature and a shortened rubbery plateau, when SiOx-Si was used as the substrate. However, sluggish flow was observed for the PS film supported by hydrogen-passivated silicon substrates (H-Si). The differences in enthalpic interactions between PS and the substrates are the reason for this divergence in the whole-chain mobility and flow ability of thin PS films deposited on SiOx-Si and H-Si surfaces. These results indicate that this approach could be a reliable rheological probe for supported thin polymeric films with different thicknesses and various substrates.
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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, China.
| | - Houkuan Tian
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Yongfeng Liang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Hao Xu
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Wei Zhang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Li Zhang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Xinping Wang
- Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
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17
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da Silva CA, Budde H, Menzel M, Wendler U, Bartke M, Weydert M, Beiner M. Self-assembled structure and relaxation dynamics of diblock copolymers made of polybutadiene and styrene/butadiene rubber. RSC Adv 2016. [DOI: 10.1039/c6ra06786g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Interrelations between self-assembled structure and cooperative α dynamics are systematically studied based on two series of poly(butadiene-block-(styrene-stat-butadiene)) diblock copolymers.
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Affiliation(s)
- C. A. da Silva
- Goodyear Innovation Center Luxembourg
- L-7750 Colmar-Berg
- Luxembourg
- Martin-Luther-Universität Halle-Wittenberg
- Naturwissenschaftliche Fakultät II
| | - H. Budde
- Fraunhofer PAZ
- D-06258 Schkopau
- Germany
| | - M. Menzel
- Fraunhofer IMWS
- D-06120 Halle (Saale)
- Germany
| | | | - M. Bartke
- Fraunhofer PAZ
- D-06258 Schkopau
- Germany
| | - M. Weydert
- Goodyear Innovation Center Luxembourg
- L-7750 Colmar-Berg
- Luxembourg
| | - M. Beiner
- Martin-Luther-Universität Halle-Wittenberg
- Naturwissenschaftliche Fakultät II
- D-06099 Halle (Saale)
- Germany
- Fraunhofer IMWS
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18
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Cheng S, Mirigian S, Carrillo JMY, Bocharova V, Sumpter BG, Schweizer KS, Sokolov AP. Revealing spatially heterogeneous relaxation in a model nanocomposite. J Chem Phys 2015; 143:194704. [DOI: 10.1063/1.4935595] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Shiwang Cheng
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Stephen Mirigian
- Department of Materials Science and Chemistry, Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - Jan-Michael Y. Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Vera Bocharova
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Bobby G. Sumpter
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Kenneth S. Schweizer
- Department of Materials Science and Chemistry, Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - Alexei P. Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Chemistry, Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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19
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Casalini R, Prevosto D, Labardi M, Roland CM. Effect of Interface Interaction on the Segmental Dynamics of Poly(vinyl acetate) Investigated by Local Dielectric Spectroscopy. ACS Macro Lett 2015; 4:1022-1026. [PMID: 35596440 DOI: 10.1021/acsmacrolett.5b00488] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The segmental dynamics of poly(vinyl acetate) (PVAc) thin films were measured in the presence of an aluminum interface and in contact with an incompatible polymer, poly(4-vinylpyridine). The local dielectric relaxation was found to be faster in thin films than in the bulk; however, no differences were observed for the various interfaces, including a PVAc/air interface. These results show that capping of thin films, even with a rigid material, does not necessarily affect the dynamics, the speeding up herein for capped PVAc was equivalent to that for the air interface. The insensitivity of the dynamics to the nature of the interface affords a means to engineer thin films while maintaining desired mechanical properties. Our findings for PVAc also may explain the discordant results that have been reported in general for the effect of air versus rigid interfaces on the local segmental relaxation of thin films.
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Affiliation(s)
- R. Casalini
- Chemistry
Division, Naval Research Laboratory, Washington, D.C., United States
| | - D. Prevosto
- CNR-IPCF,
UOS
Pisa, Largo Pontecorvo 3, 56127 Pisa, Italy
| | - M. Labardi
- CNR-IPCF,
UOS
Pisa, Largo Pontecorvo 3, 56127 Pisa, Italy
| | - C. M. Roland
- Chemistry
Division, Naval Research Laboratory, Washington, D.C., United States
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20
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Lv Y, Lin Y, Chen F, Li F, Shangguan Y, Zheng Q. Chain entanglement and molecular dynamics of solution-cast PMMA/SMA blend films affected by hydrogen bonding between casting solvents and polymer chains. RSC Adv 2015. [DOI: 10.1039/c5ra06663h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The effects of intermolecular interaction between casting solvents and polymer chains on molecular entanglement and dynamics in solution-cast PMMA/SMA films were probed by rheological, dielectric and modulated DSC methods.
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Affiliation(s)
- Yuhua Lv
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- People's Republic of China
| | - 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
| | - Feng Chen
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- People's Republic of China
| | - Fang Li
- 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
| | - 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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21
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Efremov MY. Effect of free surface roughness on the apparent glass transition temperature in thin polymer films measured by ellipsometry. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:123901. [PMID: 25554303 DOI: 10.1063/1.4902565] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Ellipsometry is one of the standard methods for observation of glass transition in thin polymer films. This work proposes that sensitivity of the method to surface morphology can complicate manifestation of the transition in a few nm thick samples. Two possible mechanisms of free surface roughening in the vicinity of glass transition are discussed: roughening due to lateral heterogeneity and roughening associated with thermal capillary waves. Both mechanisms imply an onset of surface roughness in the glass transition temperature range, which affects the experimental data in a way that shifts apparent glass transition temperature. Effective medium approximation models are used to introduce surface roughness into optical calculations. The results of the optical modeling for a 5 nm thick polystyrene film on silicon are presented.
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Affiliation(s)
- Mikhail Yu Efremov
- Materials Science Center, University of Wisconsin - Madison, Madison, Wisconsin 53706, USA
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22
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Mapesa EU, Tarnacka M, Kamińska E, Adrjanowicz K, Dulski M, Kossack W, Tress M, Kipnusu WK, Kamiński K, Kremer F. Molecular dynamics of itraconazole confined in thin supported layers. RSC Adv 2014. [DOI: 10.1039/c4ra01544d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
While glassy dynamics remain largely uninfluenced by confinement, the δ-relaxation process slows down close to the glass transition.
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Affiliation(s)
| | - Magdalena Tarnacka
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
| | - Ewa Kamińska
- Department of Pharmacognosy and Phytochemistry
- School of Pharmacy and Division of Laboratory Medicine in Sosnowiec
- Medical University of Silesia in Katowice
- 41-200 Sosnowiec, Poland
| | | | - Mateusz Dulski
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
| | - Wilhelm Kossack
- Institute for Experimental Physics I
- University of Leipzig
- Leipzig, Germany
| | - Martin Tress
- Institute for Experimental Physics I
- University of Leipzig
- Leipzig, Germany
| | | | - Kamil Kamiński
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
| | - Friedrich Kremer
- Institute for Experimental Physics I
- University of Leipzig
- Leipzig, Germany
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23
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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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24
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Shavit A, Riggleman RA. Influence of Backbone Rigidity on Nanoscale Confinement Effects in Model Glass-Forming Polymers. Macromolecules 2013. [DOI: 10.1021/ma400210w] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amit Shavit
- Department of Chemical
and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania
19104, United States
| | - Robert A. Riggleman
- Department of Chemical
and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania
19104, United States
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25
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Napolitano S, Capponi S, Vanroy B. Glassy dynamics of soft matter under 1D confinement: how irreversible adsorption affects molecular packing, mobility gradients and orientational polarization in thin films. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:61. [PMID: 23797356 DOI: 10.1140/epje/i2013-13061-8] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/14/2013] [Accepted: 05/17/2013] [Indexed: 06/02/2023]
Abstract
The structural dynamics of polymers and simple liquids confined at the nanometer scale has been intensively investigated in the last two decades in order to test the validity of theories on the glass transition predicting a characteristic length scale of a few nanometers. Although this goal has not yet been reached, the anomalous behavior displayed by some systems--e.g. thin films of polystyrene exhibit reductions of Tg exceeding 70 K and a tremendous increase in the elastic modulus--has attracted a broad community of researchers, and provided astonishing advancement of both theoretical and experimental soft matter physics. 1D confinement is achieved in thin films, which are commonly treated as systems at thermodynamic equilibrium where free surfaces and solid interfaces introduce monotonous mobility gradients, extending for several molecular sizes. Limiting the discussion to finite-size and interfacial effects implies that film thickness and surface interactions should be sufficient to univocally determine the deviation from bulk behavior. On the contrary, such an oversimplified picture, although intuitive, cannot explain phenomena like the enhancement of segmental mobility in proximity of an adsorbing interface, or the presence of long-lasting metastable states in the liquid state. Based on our recent work, we propose a new picture on the dynamics of soft matter confined in ultrathin films, focusing on non-equilibrium and on the impact of irreversibly chain adsorption on the structural relaxation. We describe the enhancement of dynamics in terms of the excess in interfacial free volume, originating from packing frustration in the adsorbed layer (Guiselin brush) at t(*) ≪ 1, where t(*) is the ratio between the annealing time and the time scale of adsorption. Prolonged annealing at times exceeding the reptation time (usually t(*) ≫ 1 induces densification, and thus reduces the deviation from bulk behavior. In this Colloquium, after reviewing the experimental approaches permitting to investigate the structural relaxation of films with one, two or no free surfaces by means of dielectric spectroscopy, we propose several methods to determine gradients of mobility in thin films, and then discuss on the unexploited potential of analyses based on the time, temperature and thickness dependence of the orientational polarization via the dielectric strength.
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Affiliation(s)
- Simone Napolitano
- Laboratory of Polymer and Soft Matter Dynamics, Faculté des Sciences, Université Libre de Bruxelles, Boulevard du Triomphe, Bâtiment NO, 1050, Bruxelles, Belgium.
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26
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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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27
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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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28
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Mujtaba A, Keller M, Ilisch S, Radusch HJ, Thurn-Albrecht T, Saalwächter K, Beiner M. Mechanical Properties and Cross-Link Density of Styrene–Butadiene Model Composites Containing Fillers with Bimodal Particle Size Distribution. Macromolecules 2012. [DOI: 10.1021/ma300925p] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. Mujtaba
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
| | - M. Keller
- Zentrum für Ingenieurwissenschaften, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
| | - S. Ilisch
- Zentrum für Ingenieurwissenschaften, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
| | - H.-J. Radusch
- Zentrum für Ingenieurwissenschaften, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
| | - T. Thurn-Albrecht
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
| | - K. Saalwächter
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
| | - M. Beiner
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg,
06099 Halle (Saale), Germany
- Fraunhofer Institut für Werkstoffmechanik IWM, Walter-Hülse-Str.
1, 06120 Halle (Saale), Germany
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29
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McKenzie R, Zurawsky W, Mijovic J. Modeling dynamics of isotropic dielectrics in a laminar heterogeneous configuration. J Phys Chem B 2012; 116:4346-53. [PMID: 22432444 DOI: 10.1021/jp211047j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The predictive capabilities of models that satisfy the Weiner bounds and Hashin-Shtrikman (HS) bounds were studied for isotropic dielectrics in a laminar heterogeneous configuration oriented perpendicular to the electric field. The dynamics were investigated isothermally using broadband dielectric relaxation spectroscopy (DRS) in the frequency range of 1 MHz to 100 mHz. The molecules chosen for study were low molecular weight glass formers, glycerol, phenyl salicylate, imidazole, and dimethyl sulfoxide, and macromolecules, polymethylhydrosiloxane, polyvinylpyrrolidone-co-vinyl acetate, poly-dl-lactic acid, and poly l-lactic acid. It was found that none of the models were able to adequately predict in entirety the resultant dynamics. Of the models studied, the most successful were the HS upper bound (HSUB), the complementary universal Weiner equation (CWE), and the Lichtenecker model for the dimensional parameter, ζ = -1/2. The least successful models were the upper Weiner bound (UWB), the Neelakantaswamy, Turkman, and Sarkar (NTS) model for ζ = 1/2, and the Lichtenecker model for ζ = 1/2.
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Affiliation(s)
- Ruel McKenzie
- Othmer-Jacobs Department of Chemical and Biological Engineering, Polytechnic Institute of NYU, 6 MetroTech Center, Brooklyn, New York 11201, USA.
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30
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Moll J, Kumar SK. Glass Transitions in Highly Attractive Highly Filled Polymer Nanocomposites. Macromolecules 2012. [DOI: 10.1021/ma202218x] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joseph Moll
- Department
of Chemistry and ‡Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Sanat K. Kumar
- Department
of Chemistry and ‡Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
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31
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Inoue R, Kawashima K, Matsui K, Nakamura M, Nishida K, Kanaya T, Yamada NL. Interfacial properties of polystyrene thin films as revealed by neutron reflectivity. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:031802. [PMID: 22060395 DOI: 10.1103/physreve.84.031802] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Indexed: 05/31/2023]
Abstract
We have studied the glass transition temperature (T(g)) and molecular mobility of polystyrene (PS) thin films near the interface between the polymer thin film and substrate with bilayer thin films consisting of surface hydrogenated PS (h-PS) and bottom deuterated PS (d-PS) using neutron reflectivity. With decreasing the thickness of the bottom d-PS layer, T(g) near the interface between the polymer thin film and substrate increased compared to bulk T(g) and a drastic increase of T(g) was observed for the bottom d-PS layer <155 Å thick. The orientation of polymer chains at the interface is supposed to be related to the increase of T(g) near the interface between the polymer and substrate. The polymer chain mobility decreased with thickness even for the bottom d-PS layer with no discernible change of T(g). It is considered that the numerous contacts between polymer chains and substrate are related to the decrease of mobility near the interface between the polymer thin film and substrate.
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Affiliation(s)
- Rintaro Inoue
- Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611-0011, Japan.
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32
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Shi Z, Debenedetti PG, Stillinger FH. Properties of model atomic free-standing thin films. J Chem Phys 2011; 134:114524. [DOI: 10.1063/1.3565480] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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33
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Tress M, Erber M, Mapesa EU, Huth H, Müller J, Serghei A, Schick C, Eichhorn KJ, Voit B, Kremer F. Glassy Dynamics and Glass Transition in Nanometric Thin Layers of Polystyrene. Macromolecules 2010. [DOI: 10.1021/ma102031k] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Martin Tress
- Institute for Experimental Physics I, University of Leipzig, 04103 Leipzig, Germany
| | - Michael Erber
- Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany
| | - Emmanuel U. Mapesa
- Institute for Experimental Physics I, University of Leipzig, 04103 Leipzig, Germany
| | - Heiko Huth
- Physics Institute, University of Rostock, 18051 Rostock, Germany
| | - Jan Müller
- Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany
| | - Anatoli Serghei
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Christoph Schick
- Physics Institute, University of Rostock, 18051 Rostock, Germany
| | | | - Brigitte Voit
- Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany
| | - Friedrich Kremer
- Institute for Experimental Physics I, University of Leipzig, 04103 Leipzig, Germany
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34
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Affiliation(s)
- C. M. Roland
- Naval Research Laboratory, Chemistry Division, Code 6120, Washington, D.C. 20375-5342
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35
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Finite size effects in multilayered polymer systems: Development of PET lamellae under physical confinement. POLYMER 2010. [DOI: 10.1016/j.polymer.2010.08.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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36
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Spiess HW. Interplay of Structure and Dynamics in Macromolecular and Supramolecular Systems. Macromolecules 2010. [DOI: 10.1021/ma1005952] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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37
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Kim S, Mundra MK, Roth CB, Torkelson JM. Suppression of the Tg-Nanoconfinement Effect in Thin Poly(vinyl acetate) Films by Sorbed Water. Macromolecules 2010. [DOI: 10.1021/ma1005606] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Soyoung Kim
- Department of Chemical and Biological Engineering
| | | | | | - John M. Torkelson
- Department of Chemical and Biological Engineering
- Department of Materials Science and Engineering
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38
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Robertson CG, Hogan TE, Rackaitis M, Puskas JE, Wang X. Effect of nanoscale confinement on glass transition of polystyrene domains from self-assembly of block copolymers. J Chem Phys 2010; 132:104904. [DOI: 10.1063/1.3337910] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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