51
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Takeno H, Koizumi S. Incoherent neutron scattering study on the local dynamics in polystyrene and poly(vinyl methyl ether) blends. POLYMER 2006. [DOI: 10.1016/j.polymer.2006.06.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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52
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Colmenero J, Moreno AJ, Alegría A. Neutron scattering investigations on methyl group dynamics in polymers. Prog Polym Sci 2005. [DOI: 10.1016/j.progpolymsci.2005.08.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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53
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Triolo A, Russina O, Hardacre C, Nieuwenhuyzen M, Gonzalez MA, Grimm H. Relaxation Processes in Room Temperature Ionic Liquids: The Case of 1-Butyl-3-Methyl Imidazolium Hexafluorophosphate. J Phys Chem B 2005; 109:22061-6. [PMID: 16853864 DOI: 10.1021/jp053355j] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A detailed investigation on the nature of the relaxation processes occurring in a typical room temperature ionic liquid (RTIL), namely, 1-butyl-3-methyl imidazolium hexafluorophosphate ([bmim][PF(6)]), is reported. The study was conducted using both elastic and inelastic neutron scattering over a wide temperature range from 10 to 400 K, accessing the dynamic features of both the liquid and glassy amorphous states. In this study, the inelastic fixed energy scan technique has been applied for the first time to this class of materials. Using this technique, the existence of two relaxation processes below the glass transition and a further diffusive process occurring above the glass-liquid transition are observed. The low temperature processes are associated with methyl group rotation and butyl chain relaxation in the glassy state and have been modeled in terms of two Debye-like, Arrhenius activated processes. The high temperature process has been modeled in terms of a Kohlraush-Williams-Watts relaxation, with a distinct Vogel-Fulcher-Tamman temperature dependence. These results provide novel information that will be useful in rationalizing the observed structural and dynamical behavior of RTILs in the amorphous state.
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Affiliation(s)
- Alessandro Triolo
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche, via La Farina 237, 98123 Messina, Italy.
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54
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Roh JH, Novikov VN, Gregory RB, Curtis JE, Chowdhuri Z, Sokolov AP. Onsets of anharmonicity in protein dynamics. PHYSICAL REVIEW LETTERS 2005; 95:038101. [PMID: 16090773 DOI: 10.1103/physrevlett.95.038101] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2004] [Indexed: 05/03/2023]
Abstract
Two onsets of anharmonicity are observed in the dynamics of the protein lysozyme. One at T approximately 100 K appears in all samples regardless of hydration level and is consistent with methyl group rotation. The second, the well-known dynamical transition at T approximately 200-230 K, is only observed at a hydration level h greater than approximately 0.2 and is ascribed to the activation of an additional relaxation process. Its variation with hydration correlates well with variations of catalytic activity suggesting that the relaxation process is directly related to the activation of modes required for protein function.
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Affiliation(s)
- J H Roh
- Department of Polymer Science, The University of Akron, Akron, OH 44325-3909, USA
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55
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Cicerone MT, Soles CL. Fast dynamics and stabilization of proteins: binary glasses of trehalose and glycerol. Biophys J 2005; 86:3836-45. [PMID: 15189880 PMCID: PMC1304285 DOI: 10.1529/biophysj.103.035519] [Citation(s) in RCA: 216] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We present elastic and inelastic incoherent neutron scattering data from a series of trehalose glasses diluted with glycerol. A strong correlation with recently published protein stability data in the same series of glasses illustrates that the dynamics at Q >or= 0.71 A(-1) and omega > 200 MHz are important to stabilization of horseradish peroxidase and yeast alcohol dehydrogenase in these glasses. To the best of our knowledge, this is the first direct evidence that enzyme stability in a room temperature glass depends upon suppressing these short-length scale, high-frequency dynamics within the glass. We briefly discuss the coupling of protein motions to the local dynamics of the glass. Also, we show that T(g) alone is not a good indicator for the protein stability in this series of glasses; the glass that confers the maximum room-temperature stability does not have the highest T(g).
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Affiliation(s)
- Marcus T Cicerone
- Polymers Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8543, USA.
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56
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Adams MA, Gabrys BJ, Zajac WM, Peiffer DG. High-Resolution Incoherent Inelastic Neutron Scattering Spectra of Polyisobutylene and Polyisoprene. Macromolecules 2004. [DOI: 10.1021/ma049651w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mark A. Adams
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
| | - Barbara J. Gabrys
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
| | - Wojciech M. Zajac
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
| | - Dennis G. Peiffer
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
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57
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Russina O, Triolo A, Aihara Y, Telling MTF, Grimm H. Quasi-Elastic Neutron Scattering Investigation of Dynamics in Polymer Electrolytes. Macromolecules 2004. [DOI: 10.1021/ma0493574] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Olga Russina
- Hahn-Meitner Institut, Glienicker Str. 100, D-14109 Berlin, Germany; Istituto per i Processi Chimico-Fisici-CNR, via La Farina 237, 98123 Messina, Italy; Yuasa Corporation, 4-5-1 Ohgi-cho, Odawara 250-0001, Japan; ISIS Facility, Rutherford Appleton Laboratory, Chilton, OXON, U.K.; and Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - Alessandro Triolo
- Hahn-Meitner Institut, Glienicker Str. 100, D-14109 Berlin, Germany; Istituto per i Processi Chimico-Fisici-CNR, via La Farina 237, 98123 Messina, Italy; Yuasa Corporation, 4-5-1 Ohgi-cho, Odawara 250-0001, Japan; ISIS Facility, Rutherford Appleton Laboratory, Chilton, OXON, U.K.; and Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - Yuichi Aihara
- Hahn-Meitner Institut, Glienicker Str. 100, D-14109 Berlin, Germany; Istituto per i Processi Chimico-Fisici-CNR, via La Farina 237, 98123 Messina, Italy; Yuasa Corporation, 4-5-1 Ohgi-cho, Odawara 250-0001, Japan; ISIS Facility, Rutherford Appleton Laboratory, Chilton, OXON, U.K.; and Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - Mark T. F. Telling
- Hahn-Meitner Institut, Glienicker Str. 100, D-14109 Berlin, Germany; Istituto per i Processi Chimico-Fisici-CNR, via La Farina 237, 98123 Messina, Italy; Yuasa Corporation, 4-5-1 Ohgi-cho, Odawara 250-0001, Japan; ISIS Facility, Rutherford Appleton Laboratory, Chilton, OXON, U.K.; and Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - Hans Grimm
- Hahn-Meitner Institut, Glienicker Str. 100, D-14109 Berlin, Germany; Istituto per i Processi Chimico-Fisici-CNR, via La Farina 237, 98123 Messina, Italy; Yuasa Corporation, 4-5-1 Ohgi-cho, Odawara 250-0001, Japan; ISIS Facility, Rutherford Appleton Laboratory, Chilton, OXON, U.K.; and Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
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58
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Arrighi V, Gagliardi S, Zhang C, Ganazzoli F, Higgins JS, Ocone R, Telling MTF. A Unified Picture of the Local Dynamics of Poly(dimethylsiloxane) across the Melting Point. Macromolecules 2003. [DOI: 10.1021/ma034843x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valeria Arrighi
- Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh, UK
| | - Simona Gagliardi
- Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh, UK
| | - Chuhong Zhang
- Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh, UK
| | - Fabio Ganazzoli
- Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta“, Sez. Chimica Politecnico di Milano via L. Mancinelli 7, 20131 Milano, Italy
| | - Julia S. Higgins
- Department of Chemical Engineering and Chemical Technology, Imperial College, South Kensington Campus, London, SW7 2AZ, UK
| | - Raffaella Ocone
- Chemical Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh, UK
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59
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Triolo A, Russina O, Arrighi V, Juranyi F, Janssen S, Gordon CM. Quasielastic neutron scattering characterization of the relaxation processes in a room temperature ionic liquid. J Chem Phys 2003. [DOI: 10.1063/1.1613637] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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60
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Bée M. Localized and long-range diffusion in condensed matter: state of the art of QENS studies and future prospects. Chem Phys 2003. [DOI: 10.1016/s0301-0104(03)00257-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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61
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Arrighi V, Batt-Coutrot D, Zhang C, Telling MTF, Triolo A. Effect of tacticity on the local dynamics of polypropylene melts. J Chem Phys 2003. [DOI: 10.1063/1.1579476] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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62
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Ahumada O, Theodorou DN, Triolo A, Arrighi V, Karatasos C, Ryckaert JP. Segmental Dynamics of Atactic Polypropylene As Revealed by Molecular Simulations and Quasielastic Neutron Scattering. Macromolecules 2002. [DOI: 10.1021/ma011807u] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Oscar Ahumada
- Department of Chemical Engineering, University of Patras and ICE/HT-FORTH, GR-26500 Patras, Greece, Chemistry Department, Heriot-Watt University Edinburgh, EH14 4AS, United Kingdom, and Laboratoire de Physique des Polymères, CP223, Université Libre de Bruxelles, Boulevard de Triomphe, B-1050 Bruxelles, Belgique
| | - Doros N. Theodorou
- Department of Chemical Engineering, University of Patras and ICE/HT-FORTH, GR-26500 Patras, Greece, Chemistry Department, Heriot-Watt University Edinburgh, EH14 4AS, United Kingdom, and Laboratoire de Physique des Polymères, CP223, Université Libre de Bruxelles, Boulevard de Triomphe, B-1050 Bruxelles, Belgique
| | - Alessandro Triolo
- Department of Chemical Engineering, University of Patras and ICE/HT-FORTH, GR-26500 Patras, Greece, Chemistry Department, Heriot-Watt University Edinburgh, EH14 4AS, United Kingdom, and Laboratoire de Physique des Polymères, CP223, Université Libre de Bruxelles, Boulevard de Triomphe, B-1050 Bruxelles, Belgique
| | - Valeria Arrighi
- Department of Chemical Engineering, University of Patras and ICE/HT-FORTH, GR-26500 Patras, Greece, Chemistry Department, Heriot-Watt University Edinburgh, EH14 4AS, United Kingdom, and Laboratoire de Physique des Polymères, CP223, Université Libre de Bruxelles, Boulevard de Triomphe, B-1050 Bruxelles, Belgique
| | - Costas Karatasos
- Department of Chemical Engineering, University of Patras and ICE/HT-FORTH, GR-26500 Patras, Greece, Chemistry Department, Heriot-Watt University Edinburgh, EH14 4AS, United Kingdom, and Laboratoire de Physique des Polymères, CP223, Université Libre de Bruxelles, Boulevard de Triomphe, B-1050 Bruxelles, Belgique
| | - Jean-Paul Ryckaert
- Department of Chemical Engineering, University of Patras and ICE/HT-FORTH, GR-26500 Patras, Greece, Chemistry Department, Heriot-Watt University Edinburgh, EH14 4AS, United Kingdom, and Laboratoire de Physique des Polymères, CP223, Université Libre de Bruxelles, Boulevard de Triomphe, B-1050 Bruxelles, Belgique
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63
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Colmenero J, Alvarez F, Arbe A. Self-motion and the alpha relaxation in a simulated glass-forming polymer: crossover from Gaussian to non-Gaussian dynamic behavior. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 65:041804. [PMID: 12005863 DOI: 10.1103/physreve.65.041804] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2001] [Revised: 12/10/2001] [Indexed: 05/23/2023]
Abstract
We present fully atomistic molecular dynamics simulations for a realistic model of a glass-forming polymer: polyisoprene. The simulations are carried out at 363 K and extend until 20 ns. We calculate the self-part of the Van Hove correlation function G(s)(r,t), the mean-squared displacement <r(2)(t)>, the second-order non-Gaussian parameter alpha(2)(t), and the incoherent intermediate scattering function F(s)(Q,t) for the main chain protons. In addition, we also calculate the density-density correlation function F(Q,t)/F(Q,0) and the second-order autocorrelation function M2(t) for different C-H bonds of the main chain. alpha(2)(t) shows a broad maximum centered at a time t(*) approximately 4 ps, which corresponds to the intermediate region of <r(2)(t)> between microscopic dynamics and sublinear diffusion. The analysis of F(s)(Q,t), F(Q,t)/F(Q,0), and M2(t) focuses on the second slow step which is associated to the alpha relaxation. Following the usual experimental procedure this decay is described in terms of a Kohlrausch-Williams-Watts (KWW) function: A exp[-(t/tau)(beta)]. In the Q range below Q(max), where Q(max) is the value at which the static structure factor shows its first maximum, the Q dependence of the KWW relaxation time of F(s)(Q,t) follows a law tau approximately Q(-2/beta). This kind of Q dependence corresponds to a Gaussian behavior of G(s)(r,t) and F(s)(Q,t). This law has been experimentally found in this Q range for different polymers. In the higher Q range-not easily accessible experimentally-strong deviations from the Gaussian behavior manifest. This crossover from Gaussian to non-Gaussian behavior can be understood in the framework of the mode coupling theory as well as in terms of a crossover from homogeneous to heterogeneous dynamics. This last interpretation opens a possible way of rationalizing the apparent contradiction between the neutron scattering and relaxation techniques results concerning dynamical heterogeneity of the alpha relaxation.
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Affiliation(s)
- J Colmenero
- Departamento de Física de Materiales, Universidad del País Vasco UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain.
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64
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Doxastakis M, Chrissopoulou K, Aouadi A, Frick B, Lodge TP, Fytas G. Segmental dynamics of disordered styrene–isoprene tetrablock copolymers. J Chem Phys 2002. [DOI: 10.1063/1.1452109] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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65
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Bée M, Djurado D, Combet J, Gonzalez M. Dynamics of camphor sulphonic acid: a quasielastic neutron scattering study. Chem Phys 2002. [DOI: 10.1016/s0301-0104(02)00313-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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66
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Soles CL, Douglas JF, Wu WL, Dimeo RM. Incoherent neutron scattering and the dynamics of confined polycarbonate films. PHYSICAL REVIEW LETTERS 2002; 88:037401. [PMID: 11801085 DOI: 10.1103/physrevlett.88.037401] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2001] [Indexed: 05/23/2023]
Abstract
Incoherent elastic neutron scattering measurements are performed on thin (75 to 1015 A) polycarbonate films supported on Si wafers. We find that the mean-square atomic displacement <u(2)> is diminished by thin film confinement. For film thicknesses comparable to the unperturbed dimensions of the macromolecule, we observe two characteristic crossover temperatures in <u(2)> as a function of temperature T, one above and the other below the bulk T(g). Furthermore, the harmonic force constant kappa, defined by the low temperature dependence of <u(2)> (i.e., kappa approximately k(B)T/<u(2)>), increases as the film thickness decreases. These observations suggest that the atoms are more strongly localized in the thin supported films.
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Affiliation(s)
- C L Soles
- NIST Polymers Division, Gaithersburg, Maryland 20899-8541, USA
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67
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Karatasos K, Ryckaert JP, Ricciardi R, Lauprêtre F. Methyl Dynamics and β-Relaxation in Polyisobutylene: Comparison between Experiment and Molecular Dynamics Simulations. Macromolecules 2002. [DOI: 10.1021/ma011290m] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. Karatasos
- Department of Physics, Polymer Physics CP-223, Université Libre de Bruxelles, Bd. du Triomphe, 1050 Brussels, Belgium; and Laboratoire de Recherche sur les Polymères, CNRS, 2 à 8 rue Henri Dunant, 94320 Thiais, France
| | - J.-P. Ryckaert
- Department of Physics, Polymer Physics CP-223, Université Libre de Bruxelles, Bd. du Triomphe, 1050 Brussels, Belgium; and Laboratoire de Recherche sur les Polymères, CNRS, 2 à 8 rue Henri Dunant, 94320 Thiais, France
| | - R. Ricciardi
- Department of Physics, Polymer Physics CP-223, Université Libre de Bruxelles, Bd. du Triomphe, 1050 Brussels, Belgium; and Laboratoire de Recherche sur les Polymères, CNRS, 2 à 8 rue Henri Dunant, 94320 Thiais, France
| | - F. Lauprêtre
- Department of Physics, Polymer Physics CP-223, Université Libre de Bruxelles, Bd. du Triomphe, 1050 Brussels, Belgium; and Laboratoire de Recherche sur les Polymères, CNRS, 2 à 8 rue Henri Dunant, 94320 Thiais, France
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68
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Zorn R, Frick B, Fetters LJ. Quasielastic neutron scattering study of the methyl group dynamics in polyisoprene. J Chem Phys 2002. [DOI: 10.1063/1.1424319] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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69
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Moreno AJ, Alegrı́a A, Colmenero J, Prager M, Grimm H, Frick B. Methyl group dynamics in glassy toluene: A neutron scattering study. J Chem Phys 2001. [DOI: 10.1063/1.1413742] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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70
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Carlsson P, Zorn R, Andersson D, Farago B, Howells WS, Börjesson L. The segmental dynamics of a polymer electrolyte investigated by coherent quasielastic neutron scattering. J Chem Phys 2001. [DOI: 10.1063/1.1370073] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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71
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Moreno AJ, Alegría A, Colmenero J, Frick B. Methyl Group Dynamics in Poly(methyl methacrylate): From Quantum Tunneling to Classical Hopping. Macromolecules 2001. [DOI: 10.1021/ma0100854] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. J. Moreno
- Departamento de Física de Materiales y Centro Mixto CSIC-UPV/EHU, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - A. Alegría
- Departamento de Física de Materiales y Centro Mixto CSIC-UPV/EHU, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - J. Colmenero
- Departamento de Física de Materiales y Centro Mixto CSIC-UPV/EHU, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - B. Frick
- Institute Laue Langevin, BP 156X, F-38042 Grenoble, France
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72
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Alvarez F, Arbe A, Colmenero J. Methyl group dynamics above the glass transition temperature: a molecular dynamics simulation in polyisoprene. Chem Phys 2000. [DOI: 10.1016/s0301-0104(00)00225-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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73
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Alvarez F, Alegría A, Colmenero J, Nicholson TM, Davies GR. Origin of the Distribution of Potential Barriers for Methyl Group Dynamics in Glassy Polymers: A Molecular Dynamics Simulation in Polyisoprene. Macromolecules 2000. [DOI: 10.1021/ma9919256] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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74
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Kanaya T, Teraguchi M, Masuda T, Kaji K. Local mobility of substituted polyacetylenes measured by quasielastic neutron scattering and its relationship with gas permeability. POLYMER 1999. [DOI: 10.1016/s0032-3861(99)00257-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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75
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76
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Mukhopadhyay R, Alegría A, Colmenero J, Frick B. Methyl Group Dynamics in Poly(vinyl acetate): A Neutron Scattering Study. Macromolecules 1998. [DOI: 10.1021/ma970575p] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- R. Mukhopadhyay
- Departamento de Física de Materiales, Facultad de Química, Universidad del País Vasco, Apartado 1072, 20080 San Sebastián, Spain
| | - A. Alegría
- Departamento de Física de Materiales, Facultad de Química, Universidad del País Vasco, Apartado 1072, 20080 San Sebastián, Spain
| | - J. Colmenero
- Departamento de Física de Materiales, Facultad de Química, Universidad del País Vasco, Apartado 1072, 20080 San Sebastián, Spain
| | - B. Frick
- Institute Laue Langevin, BP 156X, F-38042 Grenoble, France
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77
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Hansen J, Kanaya T, Nishida K, Kaji K, Tanaka K, Yamaguchi A. Role of vibrational softening in fast dynamics of an amorphous polyimide far below Tg. J Chem Phys 1998. [DOI: 10.1063/1.476055] [Citation(s) in RCA: 13] [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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78
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Szcześniak E, Głowinkowski S, Suchański W, Jurga S. Dynamics of glass-forming di-n-butyl phthalate as studied by NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 1997; 8:73-79. [PMID: 9203281 DOI: 10.1016/s0926-2040(96)01292-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Spin-lattice relaxation times T1 and nuclear Overhauser effect (NOE) enhancement factors for the individual ring carbons in di-n-butyl phthalate (DBF) show that the reorientational correlation function corresponding to the global dynamics in supercooled liquid can be described by a Davidson-Cole distribution. Measurements of proton spin-lattice relaxation times T1 and T1p, as well as 1H NMR spectra at temperatures below the glass transition temperature, Tg, reveal that the same distribution holds also for description of local dynamics in glassy DBF. The activation parameters of the motions detected are derived.
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Affiliation(s)
- E Szcześniak
- Institute of Physics, A. Mickiewicz University, Poznań, Poland
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Glowinkowski S, Jurga S, Suchanski W, Szczesniak E. Local and global dynamics in the glass-forming di-isobutyl phthalate as studied by 1H NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 1997; 7:313-317. [PMID: 9176936 DOI: 10.1016/s0926-2040(96)01266-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Spin-lattice relaxation times T1 and T1p as well as 1H NMR spectra have been employed to study the dynamics of the glass-forming di-isobutyl phthalate in the temperature range extending from 100 K, through the glass transition temperature Tg, up to 340 K. Below Tg NMR relaxation is governed by local dynamics and may be attributed to rotation of methyl groups at low temperatures and to motion of isobutyl groups in the intermediate temperature interval. Above Tg the main relaxation mechanism is provided by overall molecular motion. The observed relaxation behavior is explained by motional models assuming asymmetrical distributions of correlation times. The motional parameters obtained from Davidson-Cole distribution, which yields the best fit of the data at all temperatures are given.
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Affiliation(s)
- S Glowinkowski
- Institute of Physics A. Mickiewicz University, Poznan, Poland
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Fytas G, Meier G, Richter D. Segmental mobilities in an athermal diblock copolymer melt far above Tg by incoherent neutron scattering. J Chem Phys 1996. [DOI: 10.1063/1.471962] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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81
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Frick B, Buchenau U, Richter D. Boson peak and fast relaxation process near the glass transition in polystyrene. Colloid Polym Sci 1995. [DOI: 10.1007/bf00656884] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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82
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Frick B, Richter D. The Microscopic Basis of the Glass Transition in Polymers from Neutron Scattering Studies. Science 1995; 267:1939-45. [PMID: 17770103 DOI: 10.1126/science.267.5206.1939] [Citation(s) in RCA: 180] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Recent neutron scattering experiments on the microscopic dynamics of polymers below and above the glass transition temperature T(g) are reviewed. The results presented cover different dynamic processes appearing in glasses: local motions, vibrations, and different relaxation processes such as alpha- and beta-relaxation. For the alpha-relaxation, which occurs above T(g), it is possible to extend the time-temperature superposition principle, which is valid for polymers on a macroscopic scale, to the microscopic time scale. However, this principle is not applicable for temperatures approaching T(g). Below T(g), an inelastic excitation at a frequency of some hundred gigahertz (on the order of several wave numbers), the "boson peak," survives from a quasi-elastic overdamped scattering law at high temperatures. The connection between this boson peak and the fast dynamic process appearing near T(g) is discussed.
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