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Shamsieva A, Piyanzina I, Minisini B. Amorphous cis-1,4-polybutadiene P-V-T properties from atomistic simulations. J Mol Model 2023; 29:249. [PMID: 37452231 DOI: 10.1007/s00894-023-05658-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/08/2023] [Indexed: 07/18/2023]
Abstract
CONTEXT As a result of the diversity of microstructures encountered in cis-1,4-polybutadiene and the variety of measurement methods used, experimental values of variation of glass transition temperature (Tg) with pressure are relatively dispersed. However, atomistic simulations enable access to valuable information for very well-controlled chemistry and structures with a well-defined and systematic acquisition protocol. By varying the temperature and pressure, the specific volume of the melt was computed, yielding results that deviated by only 2% from experimental data. A linear relationship between Tg and pressure was observed, with Tg predicted to be 162 K at zero pressure and a rate of change of Tg with respect to pressure (dTg/dP) of 0.24 K/MPa. METHOD The atomistic dilatometry experiments were conducted on a model of amorphous cis-1,4 polybutadiene with an approximate molecular weight of 5400 g/mol using the LAMMPS code and the all-atom forcefield pcff + . The dilatometry process involved cooling and heating at a rate of 9 × 1012 K/min. The specific volume was calculated by averaging over seven independent configurations for each temperature. The Tait equation was employed to fit the specific volume evolution within the temperature range of 10 to 700 K under different pressures of 0, 60, and 100 MPa.
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Affiliation(s)
- Aigul Shamsieva
- Institute of Physics, Kazan Federal University, Kremlyovskaya St. 18, Kazan, 420008, Republic of Tatarstan, Russia
| | - Irina Piyanzina
- Institute of Physics, Kazan Federal University, Kremlyovskaya St. 18, Kazan, 420008, Republic of Tatarstan, Russia
| | - Benoit Minisini
- Materials Design SARL, 42 Avenue Verdier, 92120, Paris, Montrouge, France.
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Arrighi V, Gagliardi S, Ganazzoli F, Higgins JS, Raffaini G, Tanchawanich J, Taylor J, Telling MTF. Effect of Chain Length and Topological Constraints on Segmental Relaxation in Cyclic PDMS. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00397] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valeria Arrighi
- Institute of Chemical Sciences, School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Simona Gagliardi
- Institute of Chemical Sciences, School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Fabio Ganazzoli
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta”, Politecnico di Milano, via L. Mancinelli 7, 20131 Milano, Italy
| | - Julia S. Higgins
- Chemical Engineering Department, Imperial College London, South Kensington
Campus, London SW7 2AZ, United Kingdom
| | - Giuseppina Raffaini
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta”, Politecnico di Milano, via L. Mancinelli 7, 20131 Milano, Italy
| | - Jeerachada Tanchawanich
- Institute of Chemical Sciences, School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Jenny Taylor
- Institute of Chemical Sciences, School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Mark T. F. Telling
- ISIS, Rutherford
Appleton Laboratory, Chilton, Didcot OX11 OQX, United Kingdom
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom
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3
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Roh JH, Tyagi M, Hogan TE, Roland CM. Space-Dependent Dynamics in 1,4-Polybutadiene Nanocomposite. Macromolecules 2013. [DOI: 10.1021/ma401597r] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. H. Roh
- Chemistry Division, Code 6120, Naval Research Laboratory, Washington, D.C. 20375-5342,
United States
| | - M. Tyagi
- Center for
Neutron Research, National Institute of Standards and Technology, Gaithersburg,
Maryland 20899-6100, United States
- Department of Materials
Science
and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - T. E. Hogan
- Center for Research and Technology, Bridgestone Americas, Akron, Ohio 44317-0001, United
States
| | - C. M. Roland
- Chemistry Division, Code 6120, Naval Research Laboratory, Washington, D.C. 20375-5342,
United States
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Lyubimov IY, Guenza MG. Theoretical reconstruction of realistic dynamics of highly coarse-grained cis-1,4-polybutadiene melts. J Chem Phys 2013; 138:12A546. [DOI: 10.1063/1.4792367] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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5
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Polymer and Water Dynamics in Poly(vinyl alcohol)/Poly(methacrylate) Networks. A Molecular Dynamics Simulation and Incoherent Neutron Scattering Investigation. Polymers (Basel) 2011. [DOI: 10.3390/polym3041805] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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6
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Eremchev IY, Vainer YG, Naumov AV, Kador L. Low-temperature dynamics in amorphous polymers and low-molecular-weight glasses--what is the difference? Phys Chem Chem Phys 2010; 13:1843-8. [PMID: 21183979 DOI: 10.1039/c0cp01690j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Numerous experiments have shown that the low-temperature dynamics of a wide variety of disordered solids is qualitatively universal. However, most of these results were obtained with ensemble-averaging techniques which hide the local parameters of the dynamic processes. We used single-molecule (SM) spectroscopy for direct observation of the dynamic processes in disordered solids with different internal structure and chemical composition. The surprising result is that the dynamics of low-molecular-weight glasses and short-chain polymers does not follow, on a microscopic level, the current concept of low-temperature glass dynamics. An extra contribution to the dynamics was detected causing irreproducible jumps and drifts of the SM spectra on timescales between milliseconds and minutes. In most matrices consisting of small molecules and oligomers, the spectral dynamics was so fast that SM spectra could hardly or not at all be recorded and only irregular fluorescence flares were observed. These results provide new mechanistic insight into the behavior of glasses in general: At low temperatures, the local dynamics of disordered solids is not universal but depends on the structure and chemical composition of the material.
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Affiliation(s)
- Ivan Yu Eremchev
- Molecular Spectroscopy Department, Institute for Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow reg., 142190, Russia
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7
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Dalle-Ferrier C, Niss K, Sokolov AP, Frick B, Serrano J, Alba-Simionesco C. The Role of Chain Length in Nonergodicity Factor and Fragility of Polymers. Macromolecules 2010. [DOI: 10.1021/ma101622f] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cécile Dalle-Ferrier
- Laboratoire de Chimie Physique, Bâtiment 349, Université Paris-Sud, 91405 Orsay, France. Current address: Soft Matter group, IPkM, Heinrich Heine Universität, Düsseldorf, Germany
| | - Kristine Niss
- Laboratoire de Chimie Physique, Bâtiment 349, Université Paris-Sud, 91405 Orsay, France. Current address: Glass and Time, IMFUFA, Department of Sciences, Building 27 Roskilde University RUC Postbox 260 DK-4000 Roskilde, Denmark
| | - Alexei P. Sokolov
- Chemical Sciences Division at ORNL, Oak Ridge; and Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | | | - Jorge Serrano
- ICREA-Departament de Física Aplicada, EPSC, Universitat Politècnica de Catalunya, Esteve Terradas 15, 08860 Castelldefels, Spain
| | - Christiane Alba-Simionesco
- Laboratoire de Chimie Physique, Bâtiment 349, Université Paris-Sud, 91405 Orsay, France. Current address: Laboratoire Léon Brillouin, CEA-CNRS, Saclay, France
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8
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Pawlus S, Sokolov AP, Paluch M, Mierzwa M. Influence of Pressure on Chain and Segmental Dynamics in Polyisoprene. Macromolecules 2010. [DOI: 10.1021/ma100383r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sebastian Pawlus
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - Alexei P. Sokolov
- Chemical Sciences Division, ORNL, and Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600
| | - Marian Paluch
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - Michal Mierzwa
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
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9
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Dalle-Ferrier C, Simon S, Zheng W, Badrinarayanan P, Fennell T, Frick B, Zanotti JM, Alba-Simionesco C. Consequence of excess configurational entropy on fragility: the case of a polymer-oligomer blend. PHYSICAL REVIEW LETTERS 2009; 103:185702. [PMID: 19905814 DOI: 10.1103/physrevlett.103.185702] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Indexed: 05/28/2023]
Abstract
By taking advantage of the molecular weight dependence of the glass transition of polymers and their ability to form perfectly miscible blends, we propose a way to modify the fragility of a system, from fragile to strong, keeping the same glass properties, i.e., vibrational density of states, mean-square displacement, and local structure. Both slow and fast dynamics are investigated by calorimetry and neutron scattering in an athermal polystyrene-oligomer blend, and compared to those of a pure 17-mer polystyrene considered to be a reference, of the same Tg. Whereas the blend and the pure 17-mer have the same heat capacity in the glass and in the liquid, their fragilities differ strongly. Thus, the difference in fragility is related to an extra configurational entropy created by the mixing process and acting at a scale much larger than the interchain distance, without affecting the fast dynamics and the structure of the glass.
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Affiliation(s)
- C Dalle-Ferrier
- Laboratoire de Chimie Physique, UMR 8000, Bâtiment 349, Université, Paris-Sud, 91405 Orsay, France
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10
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Zamponi M, Wischnewski A, Monkenbusch M, Willner L, Richter D, Falus P, Farago B, Guenza MG. Cooperative dynamics in homopolymer melts: a comparison of theoretical predictions with neutron spin echo experiments. J Phys Chem B 2009; 112:16220-9. [PMID: 19072142 DOI: 10.1021/jp807035z] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present a comparison between theoretical predictions of the generalized Langevin equation for cooperative dynamics (CDGLE) and neutron spin echo data of dynamic structure factors for polyethylene melts. Experiments cover an extended range of length and time scales, providing a compelling test for the theoretical approach. Samples investigated include chains with increasing molecular weights undergoing dynamics across the unentangled to entangled transition. Measured center-of-mass (com) mean-square displacements display a crossover from subdiffusive to diffusive dynamics. The generalized Langevin equation for cooperative dynamics relates this anomalous diffusion to the presence of the interpolymer potential, which correlates the dynamics of a group of slowly diffusing molecules in a dynamically heterogeneous liquid. Theoretical predictions of the subdiffusive behavior, of its crossover to free diffusion, and of the number of macromolecules undergoing cooperative motion are in quantitative agreement with experiments.
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Affiliation(s)
- M Zamponi
- Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany
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11
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Niss K, Dalle-Ferrier C, Giordano VM, Monaco G, Frick B, Alba-Simionesco C. Glassy properties and viscous slowing down: An analysis of the correlation between nonergodicity factor and fragility. J Chem Phys 2008; 129:194513. [DOI: 10.1063/1.3005646] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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12
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Tsolou G, Mavrantzas VG, Makrodimitri ZA, Economou IG, Gani R. Atomistic Simulation of the Sorption of Small Gas Molecules in Polyisobutylene. Macromolecules 2008. [DOI: 10.1021/ma8007652] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | | | | | | | - Rafiqul Gani
- CAPEC, Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark
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13
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Narros A, Arbe A, Alvarez F, Colmenero J, Richter D. Atomic motions in the alphabeta-merging region of 1,4-polybutadiene: a molecular dynamics simulation study. J Chem Phys 2008; 128:224905. [PMID: 18554051 DOI: 10.1063/1.2937733] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present fully atomistic molecular dynamics simulations on 1,4-polybutadiene in a wide temperature range from 200 to 280 K, i.e., in the region where the alpha- and beta-relaxations merge and above. A big computational effort has been performed-especially for the lowest temperatures investigated-to extend the simulation runs to very long times (up to 1 mus for 200 K). The simulated sample has been carefully validated by using previous neutron scattering data on the real sample with similar microstructure. Inspecting the trajectories of the different hydrogens in real space, we have observed a heterogeneous dynamical behavior (each kind of hydrogen moves in a different way) with signatures of combined hopping and diffusive motions in the whole range investigated. The application of a previously proposed model [Colmenero et al., Europhys. Lett. 71, 262 (2005)] is successful and a characterization of the local motions and diffusion is possible. The comparison of our results to those reported in the literature provides a consistent scenario for polybutadiene dynamics and puts into a context the different experimental observations. We also discuss the impact of the hopping processes on the observation and interpretation of experimentally accessible magnitudes and the origin of the deviations from Gaussian behavior in this system.
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Affiliation(s)
- A Narros
- Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
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14
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Tyagi M, Arbe A, Alegría A, Colmenero J, Frick B. Dynamic Confinement Effects in Polymer Blends. A Quasielastic Neutron Scattering Study of the Slow Component in the Blend Poly(vinyl acetate)/Poly(ethylene oxide). Macromolecules 2007. [DOI: 10.1021/ma070539i] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. Tyagi
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain, Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain, and Institut Laue−Langevin, BP 156, 38042 Grenoble Cedex 9, France
| | - A. Arbe
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain, Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain, and Institut Laue−Langevin, BP 156, 38042 Grenoble Cedex 9, France
| | - A. Alegría
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain, Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain, and Institut Laue−Langevin, BP 156, 38042 Grenoble Cedex 9, France
| | - J. Colmenero
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain, Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain, and Institut Laue−Langevin, BP 156, 38042 Grenoble Cedex 9, France
| | - B. Frick
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain, Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain, and Institut Laue−Langevin, BP 156, 38042 Grenoble Cedex 9, France
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15
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Jia J, Bender JW. Friction dependence on alpha-relaxations in a tethered polymer monolayer. NANO LETTERS 2007; 7:1304-7. [PMID: 17447822 DOI: 10.1021/nl0702867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Functionalized low-molecular-weight polyisoputylene is commonly used as a lubricant additive to control low-velocity friction in clutches. The friction of tethered monolayers as a function of temperature and velocity was examined using lateral force microscopy. The friction force was found to obey time-temperature superposition, which indicates that the friction originates from a single relaxation mode. The scaling factors are identical to those obtained from neutron spin echo experiments of alpha-relaxations, linking the friction directly to segmental motion.
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Affiliation(s)
- Junhong Jia
- Department of Chemical Engineering, University of South Carolina, Columbia, South Carolina 29208, USA
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16
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Determining the Glass Transition in Polymer Melts. REVIEWS IN COMPUTATIONAL CHEMISTRY 2007. [DOI: 10.1002/9780470189078.ch1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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17
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Tsolou G, Harmandaris VA, Mavrantzas VG. Temperature and Pressure Effects on Local Structure and Chain Packing incis-1,4-Polybutadiene from Detailed Molecular Dynamics Simulations. MACROMOL THEOR SIMUL 2006. [DOI: 10.1002/mats.200500088] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Tsolou G, Harmandaris VA, Mavrantzas VG. Atomistic molecular dynamics simulation of the temperature and pressure dependences of local and terminal relaxations in cis-1,4-polybutadiene. J Chem Phys 2006; 124:084906. [PMID: 16512741 DOI: 10.1063/1.2174003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The dynamics of cis-1,4-polybutadiene (cis-1,4-PB) over a wide range of temperature and pressure conditions is explored by conducting atomistic molecular dynamics (MD) simulations with a united atom model on a 32-chain C128 cis-1,4-PB system. The local or segmental dynamics is analyzed in terms of the dipole moment time autocorrelation function (DACF) of the simulated polymer and its temperature and pressure variations, for temperatures as low as 195 K and pressures as high as 3 kbars. By Fourier transforming the DACF, the dielectric spectrum, epsilon* = epsilon' + i epsilon" = epsilon*omega, is computed and the normalized epsilon"/epsilon(max)" vs omega/omega(max) plot is analyzed on the basis of the time-temperature and time-pressure superposition principles. The relative contribution of thermal energy and volume to the segmental and chain relaxation processes are also calculated and evaluated in terms of the ratio of the activation energy at constant volume to the activation energy at constant pressure, Q(V)/Q(P). Additional results for the temperature and pressure dependences of the Rouse times describing terminal relaxation in the two polymers show that, in the regime of the temperature and pressure conditions covered here, segmental and chain relaxations are influenced similarly by the pressure and temperature variations. This is in contrast to what is measured experimentally [see, e.g., G. Floudas and T. Reisinger, J. Chem. Phys. 111, 5201 (1999); C. M. Roland et al.,J. Polym. Sci. Part B, 41, 3047 (2003)] for other, chemically more complex polymers that pressure has a stronger influence on the dynamics of segmental mode than on the dynamics of the longest normal mode, at least for the regime of temperature and pressure conditions covered in the present MD simulations.
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Affiliation(s)
- Georgia Tsolou
- Institute of Chemical Engineering and High-Temperature Chemical Processes (FORTH-ICE/HT), Patras GR 26504, Greece
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19
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Ngai K. Interpreting the dynamics of nano-confined glass-formers and thin polymer films: Importance of starting from a viable theory for the bulk. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/polb.20923] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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Macdonald JR, Phillips JC. Topological derivation of shape exponents for stretched exponential relaxation. J Chem Phys 2005; 122:074510. [PMID: 15743257 DOI: 10.1063/1.1850901] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In homogeneous (ideal) glasses, the important dimensionless stretched-exponential shape parameter beta is described by magic (not adjusted) simple fractions derived from fractal configuration spaces of effective dimension d* determined by different topological axioms (rules) in the presence (absence) of a forcing electric field. The rules are based on a new central principle for defining glassy states: equal a priori distributions of fractal residual configurational entropy. Our approach and its beta estimates are fully supported by the results of relaxation measurements involving many different glassy materials and probe methods. The present unique topological predictions for beta typically agree with observed values to approximately 1% and indicate that for field-forced conditions beta should be constant for appreciable ranges of such exogenous variables as temperature and ionic concentration, as indeed observed using appropriate frequency-domain data analysis. The present approach can also be inverted and used to test sample homogeneity and quality.
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Affiliation(s)
- J R Macdonald
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599-3255, USA
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21
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Wolff M, Magerl A, Frick B, Zabel H. Dynamics and structure in complex liquids under shear explored by neutron scattering. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:011509. [PMID: 15697610 DOI: 10.1103/physreve.71.011509] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2004] [Indexed: 05/24/2023]
Abstract
It is well established that the structural order of macromolecules can be affected by the application of shear. For example, triblock copolymers in aqueous solutions are known to aggregate for high concentrations. For increasing temperature the polymer micelles crystallize and offer a model system for the investigation of percolation and crystallization. The crystalline phases rearrange under shear. We correlate the structural assemblages of polymer micelles to the microscopic dynamics of the polymer monomers as well as to the solvent molecules at rest and under shear. We find the monomer dynamics affected by the different arrangements of the polymer micelles in aqueous solutions. For pronounced structural ordering we report on the monomer diffusion to become anisotropic under shear, with the diffusive mode in the direction of the shear gradient being slowed down with respect to that in the direction of the flow.
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Affiliation(s)
- Max Wolff
- Lehrstuhl fuer Kristallographie und Strukturphysik, Universitaet Erlangen-Nuernberg, 91054 Erlangen, Germany.
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22
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Ding Y, Novikov VN, Sokolov AP, A. Cailliaux,, Dalle-Ferrier C, Alba-Simionesco C, Frick B. Influence of Molecular Weight on Fast Dynamics and Fragility of Polymers. Macromolecules 2004. [DOI: 10.1021/ma0492420] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | | | | | - B. Frick
- Institute Laue Langevin, 38042 Grenoble, France
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23
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Bedrov D, Smith GD, Paul W. Anomalous pressure dependence of the structure factor in 1,4-polybutadiene melts: a molecular dynamics simulation study. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 70:011804. [PMID: 15324081 DOI: 10.1103/physreve.70.011804] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2004] [Indexed: 05/24/2023]
Abstract
Neutron scattering has shown the first diffraction peak in the structure factor of a 1,4-polybutadiene melt under compression to move to larger q values as expected but to decrease significantly in intensity. Simulations reveal that this behavior does not result from loss of structure in the polymer melt upon compression but rather from the generic effects of differences in the pressure dependence of the intermolecular and intramolecular contributions to the melt structure factor and differences in the pressure dependence of the partial structure factors for carbon-carbon and carbon-deuterium intermolecular correlations. This anomalous pressure dependence is not seen for protonated melts.
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Affiliation(s)
- Dmitry Bedrov
- Department of Materials Science and Engineering, Room 304, University of Utah, 122 S. Central Campus Drive,Salt Lake City, Utah 84112, USA
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24
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Frick B, Dosseh G, Cailliaux A, Alba-Simionesco C. Pressure dependence of the segmental relaxation of polybutadiene and polyisobutylene and influence of molecular weight. Chem Phys 2003. [DOI: 10.1016/s0301-0104(03)00236-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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