1
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Behbahani AF, Harmandaris V. Relaxation dynamics of a liquid in the vicinity of an attractive surface: The process of escaping from the surface. J Chem Phys 2024; 161:134508. [PMID: 39360684 DOI: 10.1063/5.0231689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2024] [Accepted: 09/18/2024] [Indexed: 10/04/2024] Open
Abstract
We analyze the displacements of the particles of a glass-forming molecular liquid perpendicular to a confining solid surface using extensive molecular dynamics simulations with atomistic models. In the vicinity of an attractive surface, the liquid molecules are trapped. Transient localization of liquid molecules near the surface introduces a relaxation process related to the escape of molecules from the surface into the dynamics of the interfacial liquid layer. To describe this process, we analyze several dynamical observables of the confined liquid. The self-intermediate scattering function and the mean-squared displacement of the particles located in the interfacial layer are dominated by the process of escaping from the surface. This relaxation process is also associated with a strong heterogeneity in the mobility of the interfacial particles. The studied model liquid is hydrogenated methyl methacrylate. For the confining wall, we consider different models, namely a periodic single layer of graphene and a frozen amorphous configuration of the bulk liquid (frozen wall). Near graphene, where the liquid molecules form a layered structure and adopt parallel-to-surface orientation, a clear separation between small-scale movements of the molecules near the surface and the process of escaping from the surface is observed. This is reflected in the three-step relaxation of the interfacial layer. However, near the frozen wall, where the liquid molecules do not have a preferential alignment, a clear three-step relaxation is not seen, even though the dynamical quantities are controlled by the process of escaping from the surface.
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Affiliation(s)
- Alireza F Behbahani
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, D-55099 Mainz, Germany
- Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion GR 71110, Greece
| | - Vagelis Harmandaris
- Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion GR 71110, Greece
- Computation-based Science and Technology Research Center, The Cyprus Institute, Nicosia 2121, Cyprus
- Department of Mathematics and Applied Mathematics, University of Crete, Heraklion GR 71110, Greece
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2
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Feng Y, Li R, Mbonu C, Akcora P. Effect of Oligomer Addition on Tube Dilation in Polymer Nanocomposite Melts. Macromol Rapid Commun 2024; 45:e2300620. [PMID: 38133122 DOI: 10.1002/marc.202300620] [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: 10/22/2023] [Revised: 12/15/2023] [Indexed: 12/23/2023]
Abstract
This study investigates the effect of adding oligomers on the rheological properties of polymer nanocomposite melts with the goal of enhancing the processability of nanocomposites. The scaling analysis of plateau modulus (GN ) is used in understanding the complex mechanical behavior of entangled poly(methyl acrylate) (PMA) melts upon oligomer addition. Increasing the oligomer amount led to a decrease in GN and an apparent degree of entanglement (Z) in the neat polymer melt. The particle dispersion states at two particle loadings with oligomer addition are examined in transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). The dilution exponent is found unchanged at 7 and 17 vol% particle loadings for the well-dispersed PMA-SiO2 nanocomposites compared to the neat PMA solution. These findings suggest that attractive particles with strong interfacial layers do not influence the tube dilution scaling of the polymer with the oligomer. To the contrary, composites with weak polymer-particle interfaces demonstrate phase separation of particles when oligomers are introduced and its exponent for tube dilution scaling reaches 4 at a particle loading of 17 vol%, potentially indicating that network-forming clusters influence chain entanglements in this scenario.
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Affiliation(s)
- Yi Feng
- Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Ruhao Li
- Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Christopher Mbonu
- Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Pinar Akcora
- Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
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3
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Brás AR, Arizaga A, Sokolova D, Agirre U, Viciosa MT, Radulescu A, Prévost SF, Kruteva M, Pyckhout-Hintzen W, Schmidt AM. Influence of Polymer Polarity and Association Strength on the Properties of Poly(alkyl ether)-Based Supramolecular Melts. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Ana Rita Brás
- Institute of Physical Chemistry, University of Cologne, 50939Cologne, Germany
| | - Ana Arizaga
- Institute of Physical Chemistry, University of Cologne, 50939Cologne, Germany
| | - Daria Sokolova
- Institute of Physical Chemistry, University of Cologne, 50939Cologne, Germany
- Chemistry Department, University of Basel, BPR 1096/4058Basel, Schweiz
| | - Uxue Agirre
- Institute of Physical Chemistry, University of Cologne, 50939Cologne, Germany
| | - Maria Teresa Viciosa
- IN − Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, University of Lisbon, Avenida Rovisco Pais, 1049-001Lisbon, Portugal
- Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, University of Lisbon, Avenida Rovisco Pais, 1049-001, Lisbon, Portugal
| | - Aurel Radulescu
- Jülich Centre for Neutron Science (JCNS-1), Forschungszentrum Jülich GmbH, 52428Jülich, Germany
| | | | - Margarita Kruteva
- Jülich Centre for Neutron Science (JCNS-1), Forschungszentrum Jülich GmbH, 52428Jülich, Germany
| | - Wim Pyckhout-Hintzen
- Jülich Centre for Neutron Science (JCNS-1), Forschungszentrum Jülich GmbH, 52428Jülich, Germany
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4
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Local conformations and heterogeneities in structures and dynamics of isotactic polypropylene adsorbed onto carbon fiber. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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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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Salatto D, Carrillo JMY, Endoh MK, Taniguchi T, Yavitt BM, Masui T, Kishimoto H, Tyagi M, Ribbe AE, Garcia Sakai V, Kruteva M, Sumpter BG, Farago B, Richter D, Nagao M, Koga T. Structural and Dynamical Roles of Bound Polymer Chains in Rubber Reinforcement. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01239] [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)
- Daniel Salatto
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794-2275, United States
| | - Jan-Michael Y. Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Maya K. Endoh
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794-2275, United States
| | - Takashi Taniguchi
- Graduate School of Engineering, Department of Chemical Engineering, Kyoto University, Katsura-Campus, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Benjamin M. Yavitt
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794-2275, United States
| | - Tomomi Masui
- Sumitomo Rubber Industries Ltd., 1-1, 2-chome, Tsutsui-cho, Chuo-ku, Kobe 671-0027, Japan
| | - Hiroyuki Kishimoto
- Sumitomo Rubber Industries Ltd., 1-1, 2-chome, Tsutsui-cho, Chuo-ku, Kobe 671-0027, Japan
| | - Madhusudan Tyagi
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland, 20899-6102, United States
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Alexander E. Ribbe
- Department for Polymer Science & Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Victoria Garcia Sakai
- ISIS Pulsed Neutron and Muon Facility, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, U.K
| | - Margarita Kruteva
- Jülich Centre for Neutron Science (JCNS), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Bobby G. Sumpter
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Bela Farago
- Institut Laue−Langevin, 6 rue Jules Horowitz, BP 156-38042, Grenoble Cedex 9 38000, France
| | - Dieter Richter
- Jülich Centre for Neutron Science (JCNS), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Michihiro Nagao
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland, 20899-6102, United States
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United States
| | - Tadanori Koga
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794-2275, United States
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
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7
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Jhalaria M, Huang Y, Ruzicka E, Tyagi M, Zorn R, Zamponi M, García Sakai V, Benicewicz B, Kumar S. Activated Transport in Polymer Grafted Nanoparticle Melts. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mayank Jhalaria
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Yucheng Huang
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Eric Ruzicka
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Madhusudan Tyagi
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, United States
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Reiner Zorn
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS-1) and Institute for Biological Information Processing (IBI-8), 52425 Jülich, Germany
| | - Michaela Zamponi
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at MLZ, Lichtenbergstr. 1 85748 Garching, Germany
| | - Victoria García Sakai
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, UK
| | - Brian Benicewicz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Sanat Kumar
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
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8
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Brás A, Arizaga A, Agirre U, Dorau M, Houston J, Radulescu A, Kruteva M, Pyckhout-Hintzen W, Schmidt AM. Chain-End Effects on Supramolecular Poly(ethylene glycol) Polymers. Polymers (Basel) 2021; 13:2235. [PMID: 34300992 PMCID: PMC8309292 DOI: 10.3390/polym13142235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 06/30/2021] [Accepted: 06/30/2021] [Indexed: 11/25/2022] Open
Abstract
In this work we present a fundamental analysis based on small-angle scattering, linear rheology and differential scanning calorimetry (DSC) experiments of the role of different hydrogen bonding (H-bonding) types on the structure and dynamics of chain-end modified poly(ethylene glycol) (PEG) in bulk. As such bifunctional PEG with a molar mass below the entanglement mass Me is symmetrically end-functionalized with three different hydrogen bonding (H-bonding) groups: thymine-1-acetic acid (thy), diamino-triazine (dat) and 2-ureido-4[1H]-pyrimidinone (upy). A linear block copolymer structure and a Newtonian-like dynamics is observed for PEG-thy/dat while results for PEG-upy structure and dynamics reveal a sphere and a network-like behavior, respectively. These observations are concomitant with an increase of the Flory-Huggins interaction parameter from PEG-thy/dat to PEG-upy that is used to quantify the difference between the H-bonding types. The upy association into spherical clusters is established by the Percus-Yevick approximation that models the inter-particle structure factor for PEG-upy. Moreover, the viscosity study reveals for PEG-upy a shear thickening behavior interpreted in terms of the free path model and related to the time for PEG-upy to dissociate from the upy clusters, seen as virtual crosslinks of the formed network. Moreover, a second relaxation time of different nature is also obtained from the complex shear modulus measurements of PEG-upy by the inverse of the angular frequency where G' and G'' crosses from the network-like to glass-like transition relaxation time, which is related to the segmental friction of PEG-upy polymeric network strands. In fact, not only do PEG-thy/dat and PEG-upy have different viscoelastic properties, but the relaxation times found for PEG-upy are much slower than the ones for PEG-thy/dat. However, the activation energy related to the association dynamics is very similar for both PEG-thy/dat and PEG-upy. Concerning the segmental dynamics, the glass transition temperature obtained from both rheological and calorimetric analysis is similar and increases for PEG-upy while for PEG-thy/dat is almost independent of association behavior. Our results show how supramolecular PEG properties vary by modifying the H-bonding association type and changing the molecular Flory-Huggins interaction parameter, which can be further explored for possible applications.
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Affiliation(s)
- Ana Brás
- Institute of Physical Chemistry, University of Cologne, 50939 Cologne, Germany; (A.A.); (U.A.); (M.D.); (A.M.S.)
| | - Ana Arizaga
- Institute of Physical Chemistry, University of Cologne, 50939 Cologne, Germany; (A.A.); (U.A.); (M.D.); (A.M.S.)
| | - Uxue Agirre
- Institute of Physical Chemistry, University of Cologne, 50939 Cologne, Germany; (A.A.); (U.A.); (M.D.); (A.M.S.)
| | - Marie Dorau
- Institute of Physical Chemistry, University of Cologne, 50939 Cologne, Germany; (A.A.); (U.A.); (M.D.); (A.M.S.)
| | - Judith Houston
- Jülich Centre for Neutron Science (JCNS-1) at Heinz Maier Leibnitz-Zentrum (MLZ), Forschungszentrum Jülich GmbH, 85748 Garching, Germany; (J.H.); (A.R.)
| | - Aurel Radulescu
- Jülich Centre for Neutron Science (JCNS-1) at Heinz Maier Leibnitz-Zentrum (MLZ), Forschungszentrum Jülich GmbH, 85748 Garching, Germany; (J.H.); (A.R.)
| | - Margarita Kruteva
- Jülich Centre for Neutron Science (JCNS-1), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany; (M.K.); (W.P.-H.)
| | - Wim Pyckhout-Hintzen
- Jülich Centre for Neutron Science (JCNS-1), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany; (M.K.); (W.P.-H.)
| | - Annette M. Schmidt
- Institute of Physical Chemistry, University of Cologne, 50939 Cologne, Germany; (A.A.); (U.A.); (M.D.); (A.M.S.)
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9
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10
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Abstract
AbstractQuasielastic neutron scattering (QENS) allows measurement of the molecular displacements in time and space, from pico- to tens of nanoseconds and from Ångstroms to nanometers, respectively. The method probes dynamics from fast vibrational modes down to slow diffusive motion. Every scattering experiment leads to a dynamic structure factor $$S\left( {\vec Q,\omega } \right)$$
S
Q
→
,
ω
or its spatial and temporal Fourier transform (van Hove correlation function $$G\left( {\vec r,t} \right)$$
G
r
→
,
t
). This shows exactly where the atoms are and how they move. In this manuscript the basics of the QENS method are presented and a few examples highlighting the potentials of QENS are given: (i) diffusion of liquids and gases in nano- and mesoporous materials; (ii) hydrogen dynamics in a high temperature polymer electrolyte fuel cell (HT-PEFC) and (iii) influence of the surface interactions on polymer dynamics in nanopores.
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11
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Zhang T, Winey KI, Riggleman RA. Conformation and dynamics of ring polymers under symmetric thin film confinement. J Chem Phys 2020; 153:184905. [PMID: 33187402 DOI: 10.1063/5.0024729] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Understanding the structure and dynamics of polymers under confinement has been of widespread interest, and one class of polymers that have received comparatively little attention under confinement is that of ring polymers. The properties of non-concatenated ring polymers can also be important in biological fields because ring polymers have been proven to be a good model to study DNA organization in the cell nucleus. From our previous study, linear polymers in a cylindrically confined polymer melt were found to segregate from each other as a result of the strong correlation hole effect that is enhanced by the confining surfaces. By comparison, our subsequent study of linear polymers in confined thin films at similar levels of confinements found only the onset of segregation. In this study, we use molecular dynamics simulation to investigate the chain conformations and dynamics of ring polymers under planar (1D) confinement as a function of film thickness. Our results show that conformations of ring polymers are similar to the linear polymers under planar confinement, except that ring polymers are less compressed in the direction normal to the walls. While we find that the correlation hole effect is enhanced under confinement, it is not as pronounced as the linear polymers under 2D confinement. Finally, we show that chain dynamics far above Tg are primarily affected by the friction from walls based on the monomeric friction coefficient we get from the Rouse mode analysis.
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Affiliation(s)
- Tianren Zhang
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Karen I Winey
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Robert A Riggleman
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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Ruta B, Hechler S, Neuber N, Orsi D, Cristofolini L, Gross O, Bochtler B, Frey M, Kuball A, Riegler SS, Stolpe M, Evenson Z, Gutt C, Westermeier F, Busch R, Gallino I. Wave-Vector Dependence of the Dynamics in Supercooled Metallic Liquids. PHYSICAL REVIEW LETTERS 2020; 125:055701. [PMID: 32794848 DOI: 10.1103/physrevlett.125.055701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
We present a detailed investigation of the wave-vector dependence of collective atomic motion in Au_{49}Cu_{26.9}Si_{16.3}Ag_{5.5}Pd_{2.3} and Pd_{42.5}Cu_{27}Ni_{9.5}P_{21} supercooled liquids close to the glass transition temperature. Using x-ray photon correlation spectroscopy in a previously uncovered spatial range of only a few interatomic distances, we show that the microscopic structural relaxation process mimics the structure and presents a marked slowing down at the main average interparticle distance. This behavior is accompanied by dramatic changes in the shape of the intermediate scattering functions, which suggest the presence of large dynamical heterogeneities at length scales corresponding to a few particle diameters. A ballisticlike mechanism of particle motion seems to govern the structural relaxation of the two systems in the highly viscous phase, likely associated with hopping of caged particles in agreement with theoretical studies.
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Affiliation(s)
- B Ruta
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
- ESRF-The European Synchrotron, CS40220, 38043 Grenoble, France
| | - S Hechler
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - N Neuber
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - D Orsi
- Dipartimento di Scienze Matematiche Fisiche ed Informatiche, Università degli Studi di Parma, Parma, Italy
| | - L Cristofolini
- Dipartimento di Scienze Matematiche Fisiche ed Informatiche, Università degli Studi di Parma, Parma, Italy
| | - O Gross
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - B Bochtler
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - M Frey
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - A Kuball
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - S S Riegler
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - M Stolpe
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - Z Evenson
- Heinz Maier-Leibnitz Zentrum (MLZ) and Physik Department, Technische Universität München, Lichtenbergstrasse 1, 85748 Garching, Germany
| | - C Gutt
- Department Physik, Universität Siegen, D-57072 Siegen, Germany
| | - F Westermeier
- Deutsches Elektronen Synchrotron DESY, D-22607 Hamburg, Germany
| | - R Busch
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
| | - I Gallino
- Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C6.3, 66123 Saarbrücken, Germany
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13
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Kinsey T, Mapesa E, Cosby T, He Y, Hong K, Wang Y, Iacob C, Sangoro J. Elucidating the impact of extreme nanoscale confinement on segmental and chain dynamics of unentangled poly(cis-1,4-isoprene). THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2019; 42:137. [PMID: 31650417 DOI: 10.1140/epje/i2019-11907-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Broadband dielectric spectroscopy is employed to probe dynamics in low molecular weight poly(cis-1,4-isoprene) (PI) confined in unidirectional silica nanopores with mean pore diameter, D, of 6.5 nm. Three molecular weights of PI (3, 7 and 10 kg/mol) were chosen such that the ratio of D to the polymer radius of gyration, Rg, is varied from 3.4, 2.3 to 1.9, respectively. It is found that the mean segmental relaxation rate remains bulk-like but an additional process arises at lower frequencies with increasing molecular weight (decreasing D/Rg. In contrast, the mean relaxation rates of the end-to-end dipole vector corresponding to chain dynamics are found to be slightly slower than that in the bulk for the systems approaching D/Rg ∼ 2, but faster than the bulk for the polymer with the largest molecular weight. The analysis of the spectral shapes of the chain relaxation suggests that the resulting dynamics of the 10kg/mol PI confined at length-scales close to that of the Rg are due to non-ideal chain conformations under confinement decreasing the chain relaxation times. The understanding of these faster chain dynamics of polymers under extreme geometrical confinement is necessary in designing nanodevices that contain polymeric materials within substrates approaching the molecular scale.
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Affiliation(s)
- Thomas Kinsey
- Department of Chemical and Biomolecular Engineering, University of Tennessee, 37996, Knoxville, TN, USA
| | - Emmanuel Mapesa
- Department of Chemical and Biomolecular Engineering, University of Tennessee, 37996, Knoxville, TN, USA
| | - Tyler Cosby
- Department of Chemical and Biomolecular Engineering, University of Tennessee, 37996, Knoxville, TN, USA
| | - Youjun He
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - Kunlun Hong
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - Yangyang Wang
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - Ciprian Iacob
- National Research and Development Institute for Cryogenic and Isotopic Technologies, ICSI Rm. Valcea, Rm. Valcea, Romania
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, 76128, Karlsruhe, Germany
| | - Joshua Sangoro
- Department of Chemical and Biomolecular Engineering, University of Tennessee, 37996, Knoxville, TN, USA.
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14
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Zhang T, Winey KI, Riggleman RA. Polymer Conformations and Dynamics under Confinement with Two Length Scales. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01779] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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15
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Beckmann PA, Ford J, Malachowski WP, McGhie AR, Moore CE, Rheingold AL, Sloan GJ, Szewczyk ST. Proton Spin-Lattice Relaxation in Organic Molecular Solids: Polymorphism and the Dependence on Sample Preparation. Chemphyschem 2018; 19:2423-2436. [PMID: 29956438 DOI: 10.1002/cphc.201800237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Indexed: 11/07/2022]
Abstract
We report solid-state nuclear magnetic resonance 1 H spin-lattice relaxation, single-crystal X-ray diffraction, powder X-ray diffraction, field emission scanning electron microscopy, and differential scanning calorimetry in solid samples of 2-ethylanthracene (EA) and 2-ethylanthraquinone (EAQ) that have been physically purified in different ways from the same commercial starting compounds. The solid-state 1 H spin-lattice relaxation is always non-exponential at high temperatures as expected when CH3 rotation is responsible for the relaxation. The 1 H spin-lattice relaxation experiments are very sensitive to the "several-molecule" (clusters) structure of these van der Waals molecular solids. In the three differently prepared samples of EAQ, the relaxation also becomes very non-exponential at low temperatures. This is very unusual and the decay of the nuclear magnetization can be fitted with both a stretched exponential and a double exponential. This unusual result correlates with the powder X-ray diffractometry results and suggests that the anomalous relaxation is due to crystallites of two (or more) different polymorphs (concomitant polymorphism).
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Affiliation(s)
- Peter A Beckmann
- Department of Physics, Bryn Mawr College, Bryn Mawr, Pennsylvania, USA
| | - Jamie Ford
- Nanoscale Characterization Facility Singh Center for Nanotechnology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Andrew R McGhie
- Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Curtis E Moore
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA
| | - Arnold L Rheingold
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA
| | - Gilbert J Sloan
- Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steven T Szewczyk
- Department of Materials Science and Engineering School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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16
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Berrod Q, Lagrené K, Ollivier J, Zanotti JM. Inelastic and quasi-elastic neutron scattering. Application to soft-matter. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201818805001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Microscopic dynamical events control many of the physical processes at play in condensed matter: transport, magnetism, catalysis and even function of biological assemblies. Inelastic (INS) and Quasi-Elastic Neutron Scattering (QENS) are irreplaceable probes of these phenomena. These experimental techniques reveal the displacements of atoms and molecules over distances spanning from angstroms to a few tens of nanometers, on time scales ranging from a fraction of picoseconds to microseconds. In this context, the different INS and QENS machines (Time-of-Flight (ToF), Backscattering (BS) and Neutron spin-echo (NSE)) stand at a central position. After introducing an underlying basic theoretical toolbox for neutron scattering, the principles and key elements of a ToF measurement are described. While, here, we mainly focus on disk choppers spectrometers, all the INS/QENS instruments share a common ground: they directly and simultaneously probe correlation functions in both time and space, so that the scattering vector (Q) dependence of the systems characteristic time(s) can be measured. To illustrate, the potentialities of the technique in the field of soft-matter, we show a multiscale approach of the dynamics of a polymer melt. The system is probed from the molecular to the mesoscopic scale (1 ps to 0.6 μs and 0.1 to 40 nm), in bulk and under nanometric confinement. We address the different dynamical modes of a high mass entangled polymer chain: local monomer dynamics, Rouse modes up to the reptation process. This study exemplifies that, used in conjunction with hydrogen/deuterium isotopic effects, high resolution QENS can be bridged to the Zero Average Contrast (ZAC) method to probe, in a non destructive way, the dynamics of a single polymer chain in bulk but also under severe nanometric confinement. Connection and complementarity of the neutron derived analysis with Pulsed-Field Gradient and Relaxation NMR techniques are discussed.
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17
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Solar M, Binder K, Paul W. Relaxation processes and glass transition of confined polymer melts: A molecular dynamics simulation of 1,4-polybutadiene between graphite walls. J Chem Phys 2018; 146:203308. [PMID: 28571361 DOI: 10.1063/1.4975390] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Molecular dynamics simulations of a chemically realistic model for 1,4-polybutadiene in a thin film geometry confined by two graphite walls are presented. Previous work on melts in the bulk has shown that the model faithfully reproduces static and dynamic properties of the real material over a wide temperature range. The present work studies how these properties change due to nano-confinement. The focus is on orientational correlations observable in nuclear magnetic resonance experiments and on the local intermediate incoherent neutron scattering function, Fs(qz, z, t), for distances z from the graphite walls in the range of a few nanometers. Temperatures from about 2Tg down to about 1.15Tg, where Tg is the glass transition temperature in the bulk, are studied. It is shown that weakly attractive forces between the wall atoms and the monomers suffice to effectively bind a polymer coil that is near the wall. For a wide regime of temperatures, the Arrhenius-like adsorption/desorption kinetics of the monomers is the slowest process, while very close to Tg the Vogel-Fulcher-Tammann-like α-relaxation takes over. The α-process is modified only for z≤1.2 nm due to the density changes near the walls, less than expected from studies of coarse-grained (bead-spring-type) models. The weakness of the surface effects on the glass transition in this case is attributed to the interplay of density changes near the wall with the torsional potential. A brief discussion of pertinent experiments is given.
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Affiliation(s)
- M Solar
- Institut Charles Sadron, Université Strasbourg, F-67034 Strasbourg, France
| | - K Binder
- Institut für Physik, Johannes Gutenberg-Universität, D-55099 Mainz, Germany
| | - W Paul
- Institut für Physik, Martin Luther-Universität, D-06099 Halle, Germany
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18
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Golitsyn Y, Schneider GJ, Saalwächter K. Reduced-mobility layers with high internal mobility in poly(ethylene oxide)-silica nanocomposites. J Chem Phys 2018; 146:203303. [PMID: 28571377 DOI: 10.1063/1.4974768] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A series of poly(ethylene oxide) nanocomposites with spherical silica was studied by proton NMR spectroscopy, identifying and characterizing reduced-mobility components arising from either room-temperature lateral adsorption or possibly end-group mediated high-temperature bonding to the silica surface. The study complements earlier neutron-scattering results for some of the samples. The estimated thickness of a layer characterized by significant internal mobility resembling backbone rotation ranges from 2 nm for longer (20 k) chains adsorbed on 42 nm diameter particles to 0.5 nm and below for shorter (2 k) chains on 13 nm particles. In the latter case, even lower adsorbed amounts are found when hydroxy endgroups are replaced by methyl endgroups. Both heating and water addition do not lead to significant changes of the observables, in contrast to other systems such as acrylate polymers adsorbed to silica, where temperature- and solvent-induced softening associated with a glass transition temperature gradient was evidenced. We highlight the actual agreement and complementarity of NMR and neutron scattering results, with the earlier ambiguities mainly arising from different sensitivities to the component fractions and the details of their mobility.
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Affiliation(s)
- Yury Golitsyn
- Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Street 7, D-06120 Halle, Germany
| | - Gerald J Schneider
- Department of Chemistry and Department of Physics, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Kay Saalwächter
- Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Street 7, D-06120 Halle, Germany
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19
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Molecular self-assembly of one-dimensional polymer nanostructures in nanopores of anodic alumina oxide templates. Prog Polym Sci 2018. [DOI: 10.1016/j.progpolymsci.2017.10.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Yao Y, Suzuki Y, Seiwert J, Steinhart M, Frey H, Butt HJ, Floudas G. Capillary Imbibition, Crystallization, and Local Dynamics of Hyperbranched Poly(ethylene oxide) Confined to Nanoporous Alumina. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01843] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Yang Yao
- Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
| | - Yasuhito Suzuki
- Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
| | - Jan Seiwert
- Institute
of Organic Chemistry, Johannes Gutenberg-University Mainz, D-55099 Mainz, Germany
| | - Martin Steinhart
- Institut
für Chemie neuer Materialien, Universität Osnabrück, D-49069 Osnabrück, Germany
| | - Holger Frey
- Institute
of Organic Chemistry, Johannes Gutenberg-University Mainz, D-55099 Mainz, Germany
| | - Hans-Jürgen Butt
- Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
| | - George Floudas
- Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
- Department
of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
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21
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Kimmich R, Fatkullin N. Self-diffusion studies by intra- and inter-molecular spin-lattice relaxometry using field-cycling: Liquids, plastic crystals, porous media, and polymer segments. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2017; 101:18-50. [PMID: 28844220 DOI: 10.1016/j.pnmrs.2017.04.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/02/2017] [Accepted: 04/02/2017] [Indexed: 06/07/2023]
Abstract
Field-cycling NMR relaxometry is a well-established technique for probing molecular dynamics in a frequency range from typically a few kHz up to several tens of MHz. For the interpretation of relaxometry data, it is quite often assumed that the spin-lattice relaxation process is of an intra-molecular nature so that rotational fluctuations dominate. However, dipolar interactions as the main type of couplings between protons and other dipolar species without quadrupole moments can imply appreciable inter-molecular contributions. These fluctuate due to translational displacements and to a lesser degree also by rotational reorientations in the short-range limit. The analysis of the inter-molecular proton spin-lattice relaxation rate thus permits one to evaluate self-diffusion variables such as the diffusion coefficient or the mean square displacement on a time scale from nanoseconds to several hundreds of microseconds. Numerous applications to solvents, plastic crystals and polymers will be reviewed. The technique is of particular interest for polymer dynamics since inter-molecular spin-lattice relaxation diffusometry bridges the time scales of quasi-elastic neutron scattering and field-gradient NMR diffusometry. This is just the range where model-specific intra-coil mechanisms are assumed to occur. They are expected to reveal themselves by characteristic power laws for the time-dependence of the mean-square segment displacement. These can be favorably tested on this basis. Results reported in the literature will be compared with theoretical predictions. On the other hand, there is a second way for translational diffusion phenomena to affect the spin-lattice relaxation dispersion. If rotational diffusion of molecules is restricted, translational diffusion properties can be deduced even from molecular reorientation dynamics detected by intra-molecular spin-lattice relaxation. This sort of scenario will be relevant for adsorbates on surfaces or polymer segments under entanglement and chain connectivity constraints. Under such conditions, reorientations will be correlated with translational displacements leading to the so-called RMTD relaxation process (reorientation mediated by translational displacements). Applications to porous glasses, protein solutions, lipid bilayers, and clays will be discussed. Finally, we will address the intriguing fact that the various time limits of the segment mean-square displacement of polymers in some cases perfectly reproduce predictions of the tube/reptation model whereas the reorientation dynamics suggests strongly deviating power laws.
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Affiliation(s)
| | - Nail Fatkullin
- Institute of Physics, Kazan Federal University, Kazan 420008 Tatarstan, Russia
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22
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Alexandris S, Papadopoulos P, Sakellariou G, Steinhart M, Butt HJ, Floudas G. Interfacial Energy and Glass Temperature of Polymers Confined to Nanoporous Alumina. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01484] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Stelios Alexandris
- Department of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
| | - Periklis Papadopoulos
- Department of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
| | - Georgios Sakellariou
- Department of Chemistry, National and Kapodistrian University of Athens, 15771 Athens, Greece
| | - Martin Steinhart
- Institut für Chemie neuer Materialien, Universität Osnabrück, D-49069 Osnabrück, Germany
| | - Hans-Jürgen Butt
- Max Planck Institute for Polymer Research, D-55128 Mainz, Germany
| | - George Floudas
- Department of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
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23
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Affiliation(s)
- Chia-Chun Lin
- Department of Materials Science
and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
| | - Emmabeth Parrish
- Department of Materials Science
and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
| | - Russell J. Composto
- Department of Materials Science
and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
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24
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Barroso-Bujans F, Cerveny S, Palomino P, Enciso E, Rudić S, Fernandez-Alonso F, Alegria A, Colmenero J. Dynamics and Structure of Poly(ethylene oxide) Intercalated in the Nanopores of Resorcinol–Formaldehyde Resin Nanoparticles. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01285] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fabienne Barroso-Bujans
- Centro de Física
de Materiales (CSIC-UPV/EHU), Paseo
Manuel Lardizábal 5, 20018 San Sebastián, Spain
- Donostia International
Physics Center, Paseo Manuel Lardizábal
4, 20018 San Sebastián, Spain
- IKERBASQUE - Basque
Foundation for Science, María
Díaz de Haro 3, E-48013 Bilbao, Spain
| | - Silvina Cerveny
- Centro de Física
de Materiales (CSIC-UPV/EHU), Paseo
Manuel Lardizábal 5, 20018 San Sebastián, Spain
- Donostia International
Physics Center, Paseo Manuel Lardizábal
4, 20018 San Sebastián, Spain
| | - Pablo Palomino
- Departamento
de Química Física I, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain
| | - Eduardo Enciso
- Departamento
de Química Física I, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain
| | - Svemir Rudić
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Felix Fernandez-Alonso
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, United Kingdom
- Department
of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Angel Alegria
- Centro de Física
de Materiales (CSIC-UPV/EHU), Paseo
Manuel Lardizábal 5, 20018 San Sebastián, Spain
| | - Juan Colmenero
- Centro de Física
de Materiales (CSIC-UPV/EHU), Paseo
Manuel Lardizábal 5, 20018 San Sebastián, Spain
- Donostia International
Physics Center, Paseo Manuel Lardizábal
4, 20018 San Sebastián, Spain
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25
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Franz C, Lange F, Golitsyn Y, Hartmann-Azanza B, Steinhart M, Krutyeva M, Saalwächter K. Chain Dynamics and Segmental Orientation in Polymer Melts Confined to Nanochannels. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b02309] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cornelius Franz
- Institut
für Physik − NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str.
7, D-06120 Halle, Germany
| | - Frank Lange
- Institut
für Physik − NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str.
7, D-06120 Halle, Germany
| | - Yury Golitsyn
- Institut
für Physik − NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str.
7, D-06120 Halle, Germany
| | - Brigitte Hartmann-Azanza
- Institut
für Chemie neuer Materialien, Universität Osnabrück, Barbarastr.
7, D-49069 Osnabrück, Germany
| | - Martin Steinhart
- Institut
für Chemie neuer Materialien, Universität Osnabrück, Barbarastr.
7, D-49069 Osnabrück, Germany
| | - Margarita Krutyeva
- Jülich
Centre for Neutron Science (JCNS) and Institute for Complex Systems
(ICS), Forschungszentrum Jülich GmbH, D-52428 Jülich, Germany
| | - Kay Saalwächter
- Institut
für Physik − NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str.
7, D-06120 Halle, Germany
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26
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Structure and dynamics of polymer nanocomposites studied by X-ray and neutron scattering techniques. Curr Opin Colloid Interface Sci 2015. [DOI: 10.1016/j.cocis.2015.10.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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27
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Tung WS, Composto RJ, Riggleman RA, Winey KI. Local Polymer Dynamics and Diffusion in Cylindrical Nanoconfinement. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00085] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wei-Shao Tung
- Department of Materials Science and Engineering and ‡Department of Chemical and Biomolecular
Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Russell J. Composto
- Department of Materials Science and Engineering and ‡Department of Chemical and Biomolecular
Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Robert A. Riggleman
- Department of Materials Science and Engineering and ‡Department of Chemical and Biomolecular
Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Karen I. Winey
- Department of Materials Science and Engineering and ‡Department of Chemical and Biomolecular
Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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28
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Krutyeva M, Wischnewski A, Richter D. Polymer dynamics in nanoconfinement: Interfaces and interphases. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20158302009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Carrillo JMY, Sumpter BG. Structure and dynamics of confined flexible and unentangled polymer melts in highly adsorbing cylindrical pores. J Chem Phys 2014; 141:074904. [DOI: 10.1063/1.4893055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jan-Michael Y. Carrillo
- National Center for Computational Sciences, 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 and Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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30
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Martínez-Tong DE, Cui J, Soccio M, García C, Ezquerra TA, Nogales A. Does the Glass Transition of Polymers Change Upon 3D Confinement? MACROMOL CHEM PHYS 2014. [DOI: 10.1002/macp.201400244] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
| | - Jing Cui
- Instituto de Estructura de la Materia; IEM-CSIC; C/Serrano 121 Madrid 28006 Spain
| | - Michelina Soccio
- Instituto de Estructura de la Materia; IEM-CSIC; C/Serrano 121 Madrid 28006 Spain
- Department of Materials Science and Engineering; Pennsylvania State University; University Park Pennsylvania 16802 USA
| | - Carolina García
- Instituto de Química Física Rocasolano; IQFR-CSIC; C/Serrano 119 Madrid 28006 Spain
| | - Tiberio A. Ezquerra
- Instituto de Estructura de la Materia; IEM-CSIC; C/Serrano 121 Madrid 28006 Spain
| | - Aurora Nogales
- Instituto de Estructura de la Materia; IEM-CSIC; C/Serrano 121 Madrid 28006 Spain
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31
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Martín J, Muñoz M, Encinar M, Calleja M, Martín-González M. Fabrication and mechanical characterization of semi-free-standing (conjugated) polymer thin films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:5217-5223. [PMID: 24111564 DOI: 10.1021/la4032267] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Polymers undergo severe low-dimensionality effects when they are confined to ultrathin films since most of the structural and dynamical processes involving polymer molecules are correlated to length scales of the order of nanometers. However, the real influence of the size limitation over such processes is often hard to identify as it is masked by interfacial effects. We present the fabrication of a new type of nanostructure consisting of poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) thin film that is held up exclusively over tips of poly(ether-ether-ketone) (PEEK) nanopillars. The fabrication method exploits the nonwetting behavior of PCDTBT onto an ordered PEEK nanopillar array when the mobility of the PCDTBT molecules is enhanced by a solvent annealing process. We use this new configuration to characterize the mechanical behavior of free-standing thin film regions, thus in the absence of underlaying substrate, by means of an atomic force microscope (AFM) setup. First, we study how the finite thickness and/or the presence of the underlying substrate influences the mechanical modulus of the material in the linear elastic regime. Moreover, we analyze deep indentations up to the rupture of the thin film, which allow for the measurement of important mechanical features of the nanoconfined polymer, such as its yield strain, the rupture strain, the bending rigidity, etc., which are impossible to investigate in thin films deposited on substrates.
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Affiliation(s)
- Jaime Martín
- Instituto de Microelectrónica de Madrid (IMM-CSIC) , Calle de Isaac Newton 8, Tres Cantos, 28760 Madrid, Spain
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32
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Blaszczyk-Lezak I, Hernández M, Mijangos C. One Dimensional PMMA Nanofibers from AAO Templates. Evidence of Confinement Effects by Dielectric and Raman Analysis. Macromolecules 2013. [DOI: 10.1021/ma400173q] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Iwona Blaszczyk-Lezak
- Instituto de Ciencia y Tecnología
de Polímeros, CSIC, Juan de la Cierva
3, 28006 Madrid, Spain
| | - Marianella Hernández
- Instituto de Ciencia y Tecnología
de Polímeros, CSIC, Juan de la Cierva
3, 28006 Madrid, Spain
| | - Carmen Mijangos
- Instituto de Ciencia y Tecnología
de Polímeros, CSIC, Juan de la Cierva
3, 28006 Madrid, Spain
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33
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Colmenero J, Arbe A. Recent progress on polymer dynamics by neutron scattering: From simple polymers to complex materials. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/polb.23178] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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34
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Shakirov TM, Fatkullin NF, Khalatur PG, Stapf S, Kimmich R. Computer-aided simulation of the influence of collective effects on polymer-melt dynamics in a straight cylindrical tube: Observation of the onset stage of the corset effect. POLYMER SCIENCE SERIES A 2012. [DOI: 10.1134/s0965545x12050100] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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35
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Molecular dynamics study of epoxy/clay nanocomposites: rheology and molecular confinement. JOURNAL OF POLYMER RESEARCH 2012. [DOI: 10.1007/s10965-012-9897-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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36
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Kim SY, Meyer HW, Saalwächter K, Zukoski CF. Polymer Dynamics in PEG-Silica Nanocomposites: Effects of Polymer Molecular Weight, Temperature and Solvent Dilution. Macromolecules 2012. [DOI: 10.1021/ma300439k] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- So Youn Kim
- Department of Chemical & Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
| | - Henriette W. Meyer
- Institut für Physik−NMR, Martin-Luther-Universität Halle-Wittenberg,
Betty-Heimann-Strasse 7, D-06120 Halle, Germany
| | - Kay Saalwächter
- Institut für Physik−NMR, Martin-Luther-Universität Halle-Wittenberg,
Betty-Heimann-Strasse 7, D-06120 Halle, Germany
| | - Charles F. Zukoski
- Department of Chemical & Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
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37
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Kruk D, Herrmann A, Rössler EA. Field-cycling NMR relaxometry of viscous liquids and polymers. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2012; 63:33-64. [PMID: 22546344 DOI: 10.1016/j.pnmrs.2011.08.001] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 08/17/2011] [Indexed: 05/27/2023]
Affiliation(s)
- D Kruk
- Universität Bayreuth, Experimentalphysik II, 95440 Bayreuth, Germany
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38
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Frielinghaus H, Kerscher M, Holderer O, Monkenbusch M, Richter D. Acceleration of membrane dynamics adjacent to a wall. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:041408. [PMID: 22680476 DOI: 10.1103/physreve.85.041408] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Indexed: 06/01/2023]
Abstract
The dynamics of an induced lamellar microemulsion adjacent to a planar hydrophilic surface (45 ns) were found to be three times faster compared to the bicontinuous bulk structure (133 ns). For these investigations the grazing incidence technique for neutron spin echo spectroscopy has been developed to resolve the depth dependent near surface dynamics. The observation is rationalized in terms of membrane hydrodynamics, where the flow fields reflected by the surface lead to a crossover from classical to confined fluctuations, and faster dynamics on large length scales (also known as "lubrication") are predicted.
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Affiliation(s)
- H Frielinghaus
- Jülich Centre of Neutron Science, Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, D-85747 Garching, Germany
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39
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Martín J, Hernández-Vélez M, de Abril O, Luna C, Munoz-Martin A, Vázquez M, Mijangos C. Fabrication and characterization of polymer-based magnetic composite nanotubes and nanorods. Eur Polym J 2012. [DOI: 10.1016/j.eurpolymj.2012.01.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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40
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Tailored polymer-based nanorods and nanotubes by "template synthesis": From preparation to applications. POLYMER 2012. [DOI: 10.1016/j.polymer.2012.01.028] [Citation(s) in RCA: 163] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Beckmann PA, Schneider E. Methyl group rotation,1H spin-lattice relaxation in an organic solid, and the analysis of nonexponential relaxation. J Chem Phys 2012; 136:054508. [DOI: 10.1063/1.3677183] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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42
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Lund R, Willner L, Pipich V, Grillo I, Lindner P, Colmenero J, Richter D. Equilibrium Chain Exchange Kinetics of Diblock Copolymer Micelles: Effect of Morphology. Macromolecules 2011. [DOI: 10.1021/ma200532r] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Reidar Lund
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia—San Sebastián, Spain
- Centro de Física de Materiales, Centro Mixto CSIC-UPV/EHU, Paseo Manuel de Lardizabal, 3, 20018 Donostia—San Sebastián, Spain
| | - Lutz Willner
- Jülich Centre for Neutron Science JCNS and Institute for Complex Systems ICS, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Vitaliy Pipich
- Jülich Center for Neutron Science JCNS-FRM II, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | | | | | - Juan Colmenero
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia—San Sebastián, Spain
- Centro de Física de Materiales, Centro Mixto CSIC-UPV/EHU, Paseo Manuel de Lardizabal, 3, 20018 Donostia—San Sebastián, Spain
| | - Dieter Richter
- Jülich Centre for Neutron Science JCNS and Institute for Complex Systems ICS, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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43
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Hofmann M, Herrmann A, Ok S, Franz C, Kruk D, Saalwächter K, Steinhart M, Rössler EA. Polymer Dynamics of Polybutadiene in Nanoscopic Confinement As Revealed by Field Cycling 1H NMR. Macromolecules 2011. [DOI: 10.1021/ma2002504] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Hofmann
- Experimentalphysik II, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - A. Herrmann
- Experimentalphysik II, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - S. Ok
- Institut für Chemie, Universität Osnabrück, Barbarastr. 7, D-46069 Osnabrück, Germany
| | - C. Franz
- Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 7, D 06120 Halle, Germany
| | - D. Kruk
- Experimentalphysik II, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - K. Saalwächter
- Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 7, D 06120 Halle, Germany
| | - M. Steinhart
- Institut für Chemie, Universität Osnabrück, Barbarastr. 7, D-46069 Osnabrück, Germany
| | - E. A. Rössler
- Experimentalphysik II, Universität Bayreuth, D-95440 Bayreuth, Germany
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44
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Gam S, Meth JS, Zane SG, Chi C, Wood BA, Seitz ME, Winey KI, Clarke N, Composto RJ. Macromolecular Diffusion in a Crowded Polymer Nanocomposite. Macromolecules 2011. [DOI: 10.1021/ma102463q] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sangah Gam
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
| | - Jeffrey S. Meth
- DuPont Nanocomposite Technologies, Central Research & Development, E.I. DuPont de Nemours & Co., Inc., P.O. Box 400, Wilmington, Delaware, 19880-0400, United States
| | - Steve G. Zane
- DuPont Nanocomposite Technologies, Central Research & Development, E.I. DuPont de Nemours & Co., Inc., P.O. Box 400, Wilmington, Delaware, 19880-0400, United States
| | - Changzai Chi
- DuPont Nanocomposite Technologies, Central Research & Development, E.I. DuPont de Nemours & Co., Inc., P.O. Box 400, Wilmington, Delaware, 19880-0400, United States
| | - Barbara A. Wood
- DuPont Nanocomposite Technologies, Central Research & Development, E.I. DuPont de Nemours & Co., Inc., P.O. Box 400, Wilmington, Delaware, 19880-0400, United States
| | - Michelle E. Seitz
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
| | - Karen I. Winey
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
| | - Nigel Clarke
- Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, United Kingdom
| | - Russell J. Composto
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, United States
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45
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Kimmich R, Fatkullin N. Comment on “Neutron scattering study of the dynamics of the polymer melt under nanoscopic confinement” [J. Chem. Phys. 131, 174901 (2009)]. J Chem Phys 2011; 134:057101. [DOI: 10.1063/1.3532077] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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46
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Schönhals A, Rittig F, Kärger J. Self-diffusion of poly(propylene glycol) in nanoporous glasses studied by pulsed field gradient NMR: A study of molecular dynamics and surface interactions. J Chem Phys 2011; 133:094903. [PMID: 20831334 DOI: 10.1063/1.3479905] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Pulsed field gradient NMR is applied to investigate the self-diffusion of poly(proypylene glycol) in nanoporous glasses (nominal pore sizes of 2.5-7.5 nm). In general, the diffusion is slowed down by the confinement compared to the bulk. For native pore surfaces covered by hydroxyl groups the spin echo attenuation Ψ displays a bimodal behavior versus q(2)t (q-norm of a generalized scattering vector). This was explained assuming spatial regions of different diffusivities in a two-phase model. The slow component is assigned to segments forming a surface layer close to the pore walls in which the segments have a lower mobility than those located in the center of the pores. By variation of observation time it was concluded that time constant for the dynamic exchange of segments between these two regions is around 100 ms at room temperature. For silanized pores, the bimodal behavior in the spin echo attenuation Ψ shows a stretched exponential decay versus q(2)t. The estimated diffusion coefficients decrease strongly with decreasing pore size. The temperature dependence of the diffusion coefficient can be approximated by an Arrhenius law where the activation energy increases with decreasing pore size. The observed pore size dependence for the diffusion of poly(propylene glycol) in silanized nanoporous glasses can be discussed assuming interaction and confining size effects.
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Affiliation(s)
- A Schönhals
- BAM Bundesanstalt für Materialforschung und-prüfung, Unter den Eichen 87, 12205 Berlin, Germany.
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47
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Kusmin A, Gruener S, Henschel A, de Souza N, Allgaier J, Richter D, Huber P. Polymer Dynamics in Nanochannels of Porous Silicon: A Neutron Spin Echo Study. Macromolecules 2010. [DOI: 10.1021/ma1004925] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- André Kusmin
- Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Simon Gruener
- Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Anke Henschel
- Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Nicolas de Souza
- Jülich Centre for Neutron Science, c/o TU München, Lichtenberg Strasse 1, 85747 Garching, Germany
| | - Jürgen Allgaier
- Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Dieter Richter
- Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Patrick Huber
- Experimental Physics, Saarland University, 66041 Saarbrücken, Germany
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48
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Martín J, Krutyeva M, Monkenbusch M, Arbe A, Allgaier J, Radulescu A, Falus P, Maiz J, Mijangos C, Colmenero J, Richter D. Direct observation of confined single chain dynamics by neutron scattering. PHYSICAL REVIEW LETTERS 2010; 104:197801. [PMID: 20866999 DOI: 10.1103/physrevlett.104.197801] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Indexed: 05/29/2023]
Abstract
Neutron spin echo has revealed the single chain dynamic structure factor of entangled polymer chains confined in cylindrical nanopores with chain dimensions either much larger or smaller than the lateral pore sizes. In both situations, a slowing down of the dynamics with respect to the bulk behavior is only observed at intermediate times. The results at long times provide a direct microscopic measurement of the entanglement distance under confinement. They constitute the first experimental microscopic evidence of the dilution of the total entanglement density in a polymer melt under strong confinement, a phenomenon that so far was hypothesized on the basis of various macroscopic observations.
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Affiliation(s)
- J Martín
- Instituto de Ciencia y Tecnología de Polímeros, CSIC, Madrid, Spain
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49
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Fatkullin N, Gubaidullin A, Stapf S. Features of polymer chain dynamics as revealed by intermolecular nuclear magnetic dipole-dipole interaction: Model calculations and field-cycling NMR relaxometry. J Chem Phys 2010; 132:094903. [DOI: 10.1063/1.3336832] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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