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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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2
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Elmahdy MM, Aldhafeeri KA, Ahmed MT, Azzam MA, Fahmy T. Molecular dynamics and conduction mechanism of poly(vinyl chloride‐co‐vinyl acetate‐co‐2‐hydroxypropyl acrylate) terpolymer containing ionic liquid. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Mahdy M. Elmahdy
- Department of Physics College of Science and Humanities in Al‐Kharj, Prince Sattam bin Abdulaziz University Al‐Kharj Saudi Arabia
- Department of Physics Faculty of Science, Mansoura University Mansoura Egypt
| | - Khalid A. Aldhafeeri
- Department of Physics College of Science and Humanities in Al‐Kharj, Prince Sattam bin Abdulaziz University Al‐Kharj Saudi Arabia
| | - Moustafa T. Ahmed
- Department of Physics College of Science and Humanities in Al‐Kharj, Prince Sattam bin Abdulaziz University Al‐Kharj Saudi Arabia
- Polymer Research Group Department of Physics, Faculty of Science, Mansoura University Egypt
| | - Maged A. Azzam
- Department of Chemistry College of Science and Humanities in Al‐Kharj, Prince Sattam bin Abdulaziz University Al‐Kharj Saudi Arabia
| | - Tarek Fahmy
- Polymer Research Group Department of Physics, Faculty of Science, Mansoura University Egypt
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3
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Mei B, Zhou Y, Schweizer KS. Experimental Tests of a Theoretically Predicted Noncausal Correlation between Dynamics and Thermodynamics in Glass-forming Polymer Melts. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01633] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Baicheng Mei
- Department of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Material Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Yuxing Zhou
- Department of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Material Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Kenneth S. Schweizer
- Department of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
- Material Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
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4
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Romo‐Uribe A. Acrylic‐styrene/montmorillonite nanocomposites. Melt viscoelasticity and chain dynamics in nanoconfinement. POLYM ADVAN TECHNOL 2021. [DOI: 10.1002/pat.5374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Angel Romo‐Uribe
- Research & Development, Advanced Science & Technology Division Johnson & Johnson Vision Care Inc. Jacksonville Florida USA
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5
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Wu G, Liu Y, Shi G. New Experimental Evidence for Thermodynamic Links to the Kinetic Fragility of Glass-Forming Polymers. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00670] [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)
- Guozhang Wu
- Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science & Engineering, East China University of Science & Technology, Shanghai 200237, China
| | - Yuanbiao Liu
- Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science & Engineering, East China University of Science & Technology, Shanghai 200237, China
| | - Gaopeng Shi
- Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science & Engineering, East China University of Science & Technology, Shanghai 200237, China
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6
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Talik A, Tarnacka M, Dzienia A, Kaminska E, Kaminski K, Paluch M. High-Pressure Studies on the Chain and Segmental Dynamics of a Series of Poly(propylene glycol) Derivatives. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00692] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Andrzej Dzienia
- Institute of Chemistry, University of Silesia, Szkolna 9, 40-006 Katowice, Poland
| | - Ewa Kaminska
- Department of Pharmacognosy and Phytochemistry, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, Jagiellonska 4, 41-200 Sosnowiec, Poland
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7
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Niss K, Hecksher T. Perspective: Searching for simplicity rather than universality in glass-forming liquids. J Chem Phys 2018; 149:230901. [PMID: 30579292 DOI: 10.1063/1.5048093] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This article gives an overview of experimental results on dynamics in bulk glass-forming molecular liquids. Rather than looking for phenomenology that is universal, in the sense that it is seen in all liquids, the focus is on identifying the basic characteristics, or "stylized facts," of the glass transition problem, i.e., the central observations that a theory of the physics of glass formation should aim to explain in a unified manner.
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Affiliation(s)
- Kristine Niss
- Glass and Time, IMFUFA, Department of Science and Environment, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark
| | - Tina Hecksher
- Glass and Time, IMFUFA, Department of Science and Environment, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark
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8
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Higler R, Krausser J, van der Gucht J, Zaccone A, Sprakel J. Linking slow dynamics and microscopic connectivity in dense suspensions of charged colloids. SOFT MATTER 2018; 14:780-788. [PMID: 29302676 DOI: 10.1039/c7sm01781b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The quest to unravel the nature of the glass transition, where the viscosity of a liquid increases by many orders of magnitude, while its static structure remains largely unaffected, remains unresolved. While various structural and dynamical precursors to vitrification have been identified, a predictive and quantitative description of how subtle changes at the microscopic scale give rise to the steep growth in macroscopic viscosity is missing. It was recently proposed that the presence of long-lived bonded structures within the liquid may provide the long-sought connection between local structure and global dynamics. Here we directly observe and quantify the connectivity dynamics in liquids of charged colloids en route to vitrification using three-dimensional confocal microscopy. We determine the dynamic structure from the real-space van Hove correlation function and from the particle trajectories, providing upper and lower bounds on connectivity dynamics. Based on these data, we extend Dyre's model for the glass transition to account for particle-level structural dynamics; this results in a microscopic expression for the slowing down of relaxations in the liquid that is in quantitative agreement with our experiments. These results indicate how vitrification may be understood as a dynamical connectivity transition with features that are strongly reminiscent of rigidity percolation scenarios.
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Affiliation(s)
- Ruben Higler
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, Wageningen, The Netherlands.
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9
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The glass formation of a repulsive system with also a short range attractive potential: A re-interpretation of the free volume theory. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.02.066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Ren YK, Li YT, Li LB. A theoretical interpretation of free volume at glass transition. CHINESE JOURNAL OF POLYMER SCIENCE 2017. [DOI: 10.1007/s10118-017-1968-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Jaiswal A, Egami T, Kelton KF, Schweizer KS, Zhang Y. Correlation between Fragility and the Arrhenius Crossover Phenomenon in Metallic, Molecular, and Network Liquids. PHYSICAL REVIEW LETTERS 2016; 117:205701. [PMID: 27886481 DOI: 10.1103/physrevlett.117.205701] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Indexed: 06/06/2023]
Abstract
We report the observation of a distinct correlation between the kinetic fragility index m and the reduced Arrhenius crossover temperature θ_{A}=T_{A}/T_{g} in various glass-forming liquids, identifying three distinguishable groups. In particular, for 11 glass-forming metallic liquids, we universally observe a crossover in the mean diffusion coefficient from high-temperature Arrhenius to low-temperature super-Arrhenius behavior at approximately θ_{A}≈2 which is in the stable liquid phases. In contrast, for fragile molecular liquids, this crossover occurs at much lower θ_{A}≈1.4 and usually in their supercooled states. The θ_{A} values for strong network liquids spans a wide range higher than 2. Intriguingly, the high-temperature activation barrier E_{∞} is universally found to be ∼11k_{B}T_{g} and uncorrelated with the fragility or the reduced crossover temperature θ_{A} for metallic and molecular liquids. These observations provide a way to estimate the low-temperature glassy characteristics (T_{g} and m) from the high-temperature liquid quantities (E_{∞} and θ_{A}).
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Affiliation(s)
- Abhishek Jaiswal
- Department of Nuclear, Plasma, and Radiological Engineering,University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Takeshi Egami
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA and Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - K F Kelton
- Department of Physics and Institute of Materials Science and Engineering, Washington University, St. Louis, Missouri 63130, USA
| | - Kenneth S Schweizer
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Yang Zhang
- Department of Nuclear, Plasma, and Radiological Engineering,University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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12
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Xu WS, Douglas JF, Freed KF. Influence of Cohesive Energy on Relaxation in a Model Glass-Forming Polymer Melt. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01504] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Jack F. Douglas
- Materials
Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
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13
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Xu WS, Douglas JF, Freed KF. Influence of Cohesive Energy on the Thermodynamic Properties of a Model Glass-Forming Polymer Melt. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01503] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Jack F. Douglas
- Materials
Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
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14
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Xu WS, Douglas JF, Freed KF. ENTROPY THEORY OF POLYMER GLASS-FORMATION IN VARIABLE SPATIAL DIMENSION. ADVANCES IN CHEMICAL PHYSICS 2016. [DOI: 10.1002/9781119290971.ch6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Wen-Sheng Xu
- James Franck Institute; The University of Chicago; Chicago IL USA
| | - Jack F. Douglas
- Materials Science and Engineering Division; National Institute of Standards and Technology; Gaithersburg MD USA
| | - Karl F. Freed
- James Franck Institute; The University of Chicago; Chicago IL USA
- Department of Chemistry; The University of Chicago; Chicago IL USA
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15
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Pazmiño Betancourt BA, Douglas JF, Starr FW. String model for the dynamics of glass-forming liquids. J Chem Phys 2015; 140:204509. [PMID: 24880303 DOI: 10.1063/1.4878502] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We test the applicability of a living polymerization theory to describe cooperative string-like particle rearrangement clusters (strings) observed in simulations of a coarse-grained polymer melt. The theory quantitatively describes the interrelation between the average string length L, configurational entropy Sconf, and the order parameter for string assembly Φ without free parameters. Combining this theory with the Adam-Gibbs model allows us to predict the relaxation time τ in a lower temperature T range than accessible by current simulations. In particular, the combined theories suggest a return to Arrhenius behavior near Tg and a low T residual entropy, thus avoiding a Kauzmann "entropy crisis."
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Affiliation(s)
| | - Jack F Douglas
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Francis W Starr
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
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16
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Yoon H, McKenna GB. Substrate Effects on Glass Transition and Free Surface Viscoelasticity of Ultrathin Polystyrene Films. Macromolecules 2014. [DOI: 10.1021/ma501630g] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Heedong Yoon
- Department of Chemical Engineering, Whitacre College of Engineering, Texas Tech University, Lubbock, Texas 79409-4121, United States
| | - Gregory B. McKenna
- Department of Chemical Engineering, Whitacre College of Engineering, Texas Tech University, Lubbock, Texas 79409-4121, United States
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17
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Gunasekera K, Bhosle S, Boolchand P, Micoulaut M. Superstrong nature of covalently bonded glass-forming liquids at select compositions. J Chem Phys 2013; 139:164511. [DOI: 10.1063/1.4826463] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Zhang C, Guo Y, Shepard KB, Priestley RD. Fragility of an Isochorically Confined Polymer Glass. J Phys Chem Lett 2013; 4:431-436. [PMID: 26281736 DOI: 10.1021/jz302002v] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report the effect of isochoric confinement on the dynamic fragility of a polymeric glass-former, that is, polystyrene (PS). Utilizing silica-capped PS nanospheres as a model system, the fictive temperature (Tf) and the isochoric heat capacity (Cv) are measured as a function of diameter via differential scanning calorimetry. By examining Tf as a function of cooling rate for each sample, the isochoric fragility (mv) is obtained, which decreases significantly as the diameter of the nanospheres is reduced from 260 to 129 nm. Hence, the temperature dependence of structural relaxation near the glass transition is weakened with isochoric confinement.
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Affiliation(s)
- Chuan Zhang
- †Department of Chemical and Biological Engineering and ‡Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - Yunlong Guo
- †Department of Chemical and Biological Engineering and ‡Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - Kimberly B Shepard
- †Department of Chemical and Biological Engineering and ‡Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - Rodney D Priestley
- †Department of Chemical and Biological Engineering and ‡Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
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19
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Evans CM, Torkelson JM. Major Roles of Blend Partner Fragility and Dye Placement on Component Glass Transition Temperatures: Fluorescence Study of Near-Infinitely Dilute Species in Binary Blends. Macromolecules 2012. [DOI: 10.1021/ma3014614] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christopher M. Evans
- Department
of Chemical and Biological Engineering and ‡Department of Materials Science
and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - John M. Torkelson
- Department
of Chemical and Biological Engineering and ‡Department of Materials Science
and Engineering, Northwestern University, Evanston, Illinois 60208, United States
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20
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Hunter GL, Weeks ER. The physics of the colloidal glass transition. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2012; 75:066501. [PMID: 22790649 DOI: 10.1088/0034-4885/75/6/066501] [Citation(s) in RCA: 334] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
As one increases the concentration of a colloidal suspension, the system exhibits a dramatic increase in viscosity. Beyond a certain concentration, the system is said to be a colloidal glass; structurally, the system resembles a liquid, yet motions within the suspension are slow enough that it can be considered essentially frozen. For several decades, colloids have served as a valuable model system for understanding the glass transition in molecular systems. The spatial and temporal scales involved allow these systems to be studied by a wide variety of experimental techniques. The focus of this review is the current state of understanding of the colloidal glass transition, with an emphasis on experimental observations. A brief introduction is given to important experimental techniques used to study the glass transition in colloids. We describe features of colloidal systems near and in glassy states, including increases in viscosity and relaxation times, dynamical heterogeneity and ageing, among others. We also compare and contrast the glass transition in colloids to that in molecular liquids. Other glassy systems are briefly discussed, as well as recently developed synthesis techniques that will keep these systems rich with interesting physics for years to come.
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Affiliation(s)
- Gary L Hunter
- Department of Physics, Emory University, Math and Science Center 400 Dowman Dr., N201 Atlanta, GA 30322, USA
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21
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Guo J, Simon SL. Thermodynamic scaling of polymer dynamics versus T – Tg scaling. J Chem Phys 2011; 135:074901. [DOI: 10.1063/1.3624903] [Citation(s) in RCA: 22] [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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22
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Casalini R, Fragiadakis D, Roland CM. Relaxation Dynamics of Poly(methyl acrylate) at Elevated Pressure. Macromolecules 2011. [DOI: 10.1021/ma200892f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- R. Casalini
- Chemistry Division, Code 6120, Naval Research Laboratory, Washington, D. C. 20375-5342, United States
| | - D. Fragiadakis
- Chemistry Division, Code 6120, Naval Research Laboratory, Washington, D. C. 20375-5342, United States
| | - C. M. Roland
- Chemistry Division, Code 6120, Naval Research Laboratory, Washington, D. C. 20375-5342, United States
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23
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Grassia L, Carbone MGP, D'Amore A. Modeling of the isobaric and isothermal glass transitions of polystyrene. J Appl Polym Sci 2011. [DOI: 10.1002/app.34789] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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24
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Zhao Z, Huang W, Richert R, Angell CA. Glass transition and fragility in the simple molecular glassformer CS(2) from CS(2)-S(2)Cl(2) solution studies. J Chem Phys 2010; 132:154505. [PMID: 20423187 DOI: 10.1063/1.3380833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
With an interest in finding the fragility for a simple, single component, molecular glassformer, we have determined the dielectric relaxation and glass transition behavior for a series of glasses in the CS(2)-S(2)Cl(2) and CS(2)-toluene systems. Crystallization of CS(2) can be completely avoided down to the composition 20 mol% second component, and the fragility proves almost independent of CS(2) content in each system. Since the glass temperature T(g) obtained from both thermal studies and from dielectric relaxation (using T(g,diel)=T(tau=100 s)) is quite linear over the whole composition range in each system, and since relaxation time data for pure CS(2) fall on the same master plot when scaled by the linearly extrapolated T(g) value, we deduce that pure CS(2) has the same high fragility as the binary solutions. The value is m=86, as for ortho-terphenyl (OTP). Based on observations of independent studies for the vibrational density of states (VDoS) (of inherent structures for OTP and instantaneous, at-temperature structures for CS(2)), we attribute the high fragility to an excess vibrational heat capacity (defined by C(p) (vib, excess)=dS(vib, excess)/d ln T) originating in the behavior of the low frequency modes of the VDoS (the boson peak modes). Both low frequency DoS and anharmonicity increase with increasing temperature, augmenting the configurational entropy drive to the top of the system energy landscape. The surprising implication is that fragility is determined in the vibrational, not configurational, manifold of microstates.
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Affiliation(s)
- Zuofeng Zhao
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA
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25
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Stukalin EB, Douglas JF, Freed KF. Application of the entropy theory of glass formation to poly(α-olefins). J Chem Phys 2009; 131:114905. [DOI: 10.1063/1.3216109] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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26
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Schwartz GA, Paluch M, Alegría A, Colmenero J. High pressure dynamics of polymer/plasticizer mixtures. J Chem Phys 2009; 131:044906. [PMID: 19655918 DOI: 10.1063/1.3187938] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Plasticizers are usually added to polymers to give them the desired flexibility and processability by changing the dynamical properties of the polymer chains. It is therefore important to give a quantitative description about how the dynamic behavior of a given polymer is modified by the incorporation of a second component. We analyze in this work, by means of dielectric spectroscopy, the dynamics of poly(vinyl acetate)/diethyl phthalate mixtures, at different concentrations, over a broad range of frequency, pressure, and temperature. The dynamics of these particular mixtures show only one main relaxation process contrarily to what is observed in athermal miscible polymer mixtures. From the dielectric spectra the maximum relaxation time as a function of pressure and temperature was obtained and analyzed. We studied the pressure dependence of the glass transition temperature as well as the fragility of both the neat components and the mixtures at different concentrations (on the rich polymer range). Finally, the experimental data were rationalized within the framework of an Adam-Gibbs (AG) based approach recently developed [G. A. Schwartz et al., J. Chem. Phys. 127, 154907 (2007)]. The model, originally developed for athermal blends, is here modified to take into account the non-negligible interaction between polymer and plasticizer. We found that the temperature-pressure dependence of the alpha-relaxation time is very well described by this AG extended model.
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Affiliation(s)
- Gustavo Ariel Schwartz
- Centro de Física de Materiales (CSIC-UPV/EHU)-Materials Physics Center MPC, Edificio Korta, 20018 San Sebastián, Spain.
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27
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Merabia S, Long D. Heterogeneous Dynamics and Pressure Dependence of the Dynamics in van der Waals Liquids. Macromolecules 2008. [DOI: 10.1021/ma702524j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Samy Merabia
- Laboratoire de Physique des Solides, CNRS and Université de Paris XI, Bat. 510, 91405 Orsay Cédex, France, and Departament de Fisica Fonamental, Universitat de Barcelona, Marti i Franqués 1, 08028 Barcelona, Spain
| | - Didier Long
- Laboratoire de Physique des Solides, CNRS and Université de Paris XI, Bat. 510, 91405 Orsay Cédex, France, and Departament de Fisica Fonamental, Universitat de Barcelona, Marti i Franqués 1, 08028 Barcelona, Spain
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Dudowicz J, Freed KF, Douglas JF. Generalized Entropy Theory of Polymer Glass Formation. ADVANCES IN CHEMICAL PHYSICS 2008. [DOI: 10.1002/9780470238080.ch3] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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29
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Abstract
Random first-order transition theory is used to determine the role of attractive and repulsive interactions in the dynamics of supercooled liquids. Self-consistent phonon theory, an approximate mean field treatment consistent with random first-order transition theory, is used to treat individual glassy configurations, whereas the liquid phase is treated using common liquid-state approximations. Free energies are calculated using liquid-state perturbation theory. The transition temperature, T*A, the temperature where the onset of activated behavior is predicted by mean field theory; the lower crossover temperature, T*C, where barrierless motions actually occur through fractal or stringy motions (corresponding to the phenomenological mode coupling transition temperature); and T*K, the Kauzmann temperature (corresponding to an extrapolated entropy crisis), are calculated in addition to T*g, the glass transition temperature that corresponds to laboratory cooling rates. Relationships between these quantities agree well with existing experimental and simulation data on van der Waals liquids. Both the isobaric and isochoric behavior in the supercooled regime are studied, providing results for DeltaCV and DeltaCp that can be used to calculate the fragility as a function of density and pressure, respectively. The predicted variations in the alpha-relaxation time with temperature and density conform to the empirical density-temperature scaling relations found by Casalini and Roland. We thereby demonstrate the microscopic origin of their observations. Finally, the relationship first suggested by Sastry between the spinodal temperature and the Kauzmann temperatures, as a function of density, is examined. The present microscopic calculations support the existence of an intersection of these two temperatures at sufficiently low temperatures.
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Affiliation(s)
- Randall W Hall
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70808, USA.
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30
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Schwartz GA, Colmenero J, Alegría Á. Single Component Dynamics in Miscible Poly(vinyl methyl ether)/Polystyrene Blends under Hydrostatic Pressure. Macromolecules 2007. [DOI: 10.1021/ma062609b] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gustavo A. Schwartz
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, and Departamento de Física de Materiales UPV/EHU, Centro de Física de Materiales CSIC-UPV/EHU, Facultad de Química, Apartado 1072, 20080 San Sebastián, Spain
| | - Juan Colmenero
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, and Departamento de Física de Materiales UPV/EHU, Centro de Física de Materiales CSIC-UPV/EHU, Facultad de Química, Apartado 1072, 20080 San Sebastián, Spain
| | - Ángel Alegría
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain, and Departamento de Física de Materiales UPV/EHU, Centro de Física de Materiales CSIC-UPV/EHU, Facultad de Química, Apartado 1072, 20080 San Sebastián, Spain
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31
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Chen K, Schweizer KS. Theory of relaxation and elasticity in polymer glasses. J Chem Phys 2007; 126:014904. [PMID: 17212516 DOI: 10.1063/1.2428306] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The recently developed activated barrier hopping theory of deeply supercooled polymer melts [K. S. Schweizer and E. J. Saltzman, J. Chem. Phys. 121, 1984 (2004)] is extended to the nonequilibrium glass state. Below the kinetic glass temperature T(g), the exact statistical mechanical relation between the dimensionless amplitude of long wavelength density fluctuations, S(0), and the thermodynamic compressibility breaks down. Proper extension of the theory requires knowledge of the nonequilibrium S(0) which x-ray scattering experiments find to consist of a material specific and temperature-independent quenched disorder contribution plus a vibrational contribution which varies roughly linearly with temperature. Motivated by these experiments and general landscape concepts, a simple model is proposed for S(0)(T). Deep in the glass state the form of the temperature dependence of the segmental relaxation time is found to depend sensitively on the magnitude of frozen in density fluctuations. At the (modest) sub-T(g) temperatures typically probed in experiment, an effective Arrhenius behavior is generically predicted which is of nonequilibrium origin. The change in apparent activation energy across the glass transition is determined by the amplitude of frozen density fluctuations. For values of the latter consistent with experiment, the theory predicts a ratio of effective activation energies in the range of 3-6, in agreement with multiple measurements. Calculations of the shear modulus for atactic polymethylmethacrylate above and below the glass transition temperature have also been performed. The present work provides a foundation for the formulation of predictive theories of physical aging, the influence of deformation on the alpha relaxation process, and rate-dependent nonlinear mechanical properties of thermoplastics.
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Affiliation(s)
- Kang Chen
- Department of Materials Science and Engineering, University of Illinois, Urbana, IL 61801, USA
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32
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Vyazovkin S, Sbirrazzuoli N, Dranca I. Variation in Activation Energy of the Glass Transition for Polymers of Different Dynamic Fragility. MACROMOL CHEM PHYS 2006. [DOI: 10.1002/macp.200600095] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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33
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Cangialosi D, Alegría A, Colmenero J. A thermodynamic approach to the fragility of glass-forming polymers. J Chem Phys 2006; 124:024906. [PMID: 16422647 DOI: 10.1063/1.2149853] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have connected the dynamic fragility, namely, the steepness of the relaxation-time variation upon temperature reduction, to the excess entropy and heat capacity of a large number of glass-forming polymers. The connection was obtained in a natural way from the Adam-Gibbs equation, relating the structural relaxation time to the configurational entropy. We find a clear correlation for a group of polymers. For another group of polymers, for which this correlation does not work, we emphasize the role of relaxation processes unrelated to the alpha process in affecting macroscopic thermodynamic properties. Once the residual excess entropy at the Vogel temperature is removed from the total excess entropy, the correlation between dynamic fragility and thermodynamic properties is reestablished.
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Affiliation(s)
- D Cangialosi
- Fundacion Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastian, Spain.
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34
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Dudowicz J, Freed KF, Douglas JF. Fragility of Glass-Forming Polymer Liquids. J Phys Chem B 2005; 109:21350-6. [PMID: 16853769 DOI: 10.1021/jp053693k] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The fragility of polymeric glass-forming liquids is calculated as a function of molecular structural parameters from a generalized entropy theory of polymer glass-formation that combines the Adam-Gibbs (AG) model for the rate of structural relaxation with the lattice cluster theory (LCT) for polymer melt thermodynamics. Our generalized entropy theory predicts the existence of distinct high and low temperature regimes of glass-formation that are separated by a thermodynamically well-defined crossover temperature T(I) at which the product of the configurational entropy and the temperature has an inflection point. Since the predicted temperature dependence of the configurational entropy and structural relaxation time are quite different in these temperature regimes, we introduce separate definitions of fragility for each regime. Experimentally established trends in the fragility of polymer melts with respect to variations in polymer microstructure and pressure are interpreted within our theory in terms of the accompanying changes in the chain packing efficiency.
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Affiliation(s)
- Jacek Dudowicz
- The James Franck Institute and Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, USA
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35
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Casalini R, Roland CM. Why liquids are fragile. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 72:031503. [PMID: 16241440 DOI: 10.1103/physreve.72.031503] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Indexed: 05/05/2023]
Abstract
The fragilities (T(g)-normalized temperature dependence of alpha-relaxation times) of 33 glass-forming liquids and polymers are compared for isobaric, mP, and isochoric, mV, conditions. We find that the two quantities are linearly correlated: mP = (37+/-3) + (0.84+/-0.05)mV. This result has obvious and important consequences, since the ratio mV/mP is a measure of the relative degree to which temperature and density control the dynamics. Moreover, we show that the fragility itself is a consequence of the relative interplay of temperature and density effects near T(g). Specifically, strong behavior reflects a substantial contribution from density (jammed dynamics), while the relaxation of fragile liquids is more thermally activated. Drawing on the scaling law log(tau) = I(T upsilon(gamma)), a physical interpretation of this result in terms of the intermolecular potential is offered.
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Affiliation(s)
- R Casalini
- Naval Research Laboratory, Code 6120, Washington, DC 20375-5342, USA.
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36
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Roland CM, Casalini R. Effect of chemical structure on the isobaric and isochoric fragility in polychlorinated biphenyls. J Chem Phys 2005; 122:134505. [PMID: 15847479 DOI: 10.1063/1.1863173] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Pressure-volume-temperature data, along with dielectric relaxation measurements, are reported for a series of polychlorinated biphenyls (PCB), differing in the number of chlorine atoms on their phenyl rings. Analysis of the results reveals that with increasing chlorine content, the relaxation times of the PCB become governed to a greater degree by density rho relative to the effect of temperature T. This result is consistent with the respective magnitudes of the scaling exponent gamma yielding superpositioning of the relaxation times measured at various temperatures and pressures, when plotted versus rho(gamma)/T. While at constant (atmospheric) pressure, fragilities for the various PCB are equivalent, the fragility at constant volume varies inversely with chlorine content. Evidently, the presence of bulkier chlorine atoms on the phenyl rings magnifies the effect which the density has on the relaxation dynamics.
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Affiliation(s)
- C M Roland
- Naval Research Laboratory, Chemistry Division, Code 6120, Washington, DC 20375-5342, USA.
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37
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Scaling of the segmental relaxation times of polymers and its relation to the thermal expansivity. Colloid Polym Sci 2004. [DOI: 10.1007/s00396-004-1156-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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38
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Tarjus G, Kivelson D, Mossa S, Alba-Simionesco C. Disentangling density and temperature effects in the viscous slowing down of glassforming liquids. J Chem Phys 2004; 120:6135-41. [PMID: 15267499 DOI: 10.1063/1.1649732] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a consistent picture of the respective role of density (rho) and temperature (T) in the viscous slowing down of glassforming liquids and polymers. Specifically, based in part upon a new analysis of simulation and experimental data on liquid ortho-terphenyl, we conclude that a zeroth-order description of the approach to the glass transition (in the range of experimentally accessible pressures) should be formulated in terms of a temperature-driven super-Arrhenius activated behavior rather than a density-driven congestion or jamming phenomenon. The density plays a role at a quantitative level, but its effect on the viscosity and the alpha-relaxation time can be simply described via a single parameter, an effective interaction energy that is characteristic of the high-T liquid regime; as a result, rho does not affect the "fragility" of the glassforming system.
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Affiliation(s)
- G Tarjus
- Laboratoire de Physique Theorique des Liquides, Universite Pierre et Marie Curie, 4 place Jussieu, Paris 75005, France
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39
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Roland CM, Casalini R. Temperature dependence of local segmental motion in polystyrene and its variation with molecular weight. J Chem Phys 2003. [DOI: 10.1063/1.1581850] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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40
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Roland CM, Casalini R, Santangelo P, Sekula M, Ziolo J, Paluch M. Chemical Structure and Local Segmental Dynamics in 1,2-Polybutadiene. Macromolecules 2003. [DOI: 10.1021/ma034416j] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. M. Roland
- Chemistry Division, Code 6120, Naval Research Lab, Washington, D.C. 20375-5342; Chemistry Department, George Mason University, Fairfax Virginia 22030; and Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland
| | - R. Casalini
- Chemistry Division, Code 6120, Naval Research Lab, Washington, D.C. 20375-5342; Chemistry Department, George Mason University, Fairfax Virginia 22030; and Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland
| | - P. Santangelo
- Chemistry Division, Code 6120, Naval Research Lab, Washington, D.C. 20375-5342; Chemistry Department, George Mason University, Fairfax Virginia 22030; and Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland
| | - M. Sekula
- Chemistry Division, Code 6120, Naval Research Lab, Washington, D.C. 20375-5342; Chemistry Department, George Mason University, Fairfax Virginia 22030; and Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland
| | - J. Ziolo
- Chemistry Division, Code 6120, Naval Research Lab, Washington, D.C. 20375-5342; Chemistry Department, George Mason University, Fairfax Virginia 22030; and Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland
| | - M. Paluch
- Chemistry Division, Code 6120, Naval Research Lab, Washington, D.C. 20375-5342; Chemistry Department, George Mason University, Fairfax Virginia 22030; and Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland
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41
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Frick B, Alba-Simionesco C, Andersen KH, Willner L. Influence of density and temperature on the microscopic structure and the segmental relaxation of polybutadiene. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 67:051801. [PMID: 12786169 DOI: 10.1103/physreve.67.051801] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2002] [Indexed: 05/24/2023]
Abstract
We investigate the influence of temperature and density on the local structure and the dynamics of polybutadiene by controlling both hydrostatic pressure and temperature in polarized neutron diffraction experiments on deuterated polybutadiene and in inelastic incoherent scattering experiments on protonated polybutadiene. We observe that the static structure factor S(Q) does not change along macroscopic isochores. This behavior is contrary to the relaxations observed on the nanosecond and picosecond time scales and viewed by the dynamic incoherent scattering law S(Q,omega), which differ strongly along the same thermodynamic path. We conclude that the static behavior, i.e., S(Q), is dominated by macroscopic density changes, similar to the vibrational excitations in the meV range. However, the relaxation dynamics is more sensitive to thermal energy changes. This is confirmed by the finding that lines of identical relaxation behavior (in time, shape, and Q dependence), isochrones on the 10(-9) sec time scale, clearly cross the constant density lines in the (P,T) plane. Concerning S(Q), we can reasonably relate the variation of the main-peak position to the average neighbor chain distance and deduce crude microscopic thermal expansion and compressibility coefficients. In the low-Q regime, the observed pressure and temperature variation of S(Q) exceeds the compressibility contribution and suggests the existence of additional scattering, which might originate from structural correlations arising at higher temperature and low pressure.
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Affiliation(s)
- B Frick
- Institut Laue-Langevin, 6, rue Horowitz, F-38042 Grenoble, France
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42
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Middleton TF, Wales DJ. Energy landscapes of model glasses. II. Results for constant pressure. J Chem Phys 2003. [DOI: 10.1063/1.1545096] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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43
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Casalini R, Paluch M, Roland CM. Influence of molecular structure on the dynamics of supercooled van der Waals liquids. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 67:031505. [PMID: 12689071 DOI: 10.1103/physreve.67.031505] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2002] [Revised: 10/30/2002] [Indexed: 05/24/2023]
Abstract
Dielectric spectroscopy was carried out on the van der Waals liquid, 1,1(')-di(4-methoxy-5-methylphenyl)cyclohexane (BMMPC) in the supercooled state at pressures up to 218 MPa. The excess wing in this type-A glass former exhibits a response to pressure and temperature changes that is identical to that of the primary structural relaxation peak, indicating that the two processes reflect correlated molecular motions. Under no conditions was a distinct secondary peak observed in BMMPC, unlike the structurally very similar BMPC [1,1(')-bis(p-methoxyphenyl)cyclohexane]. However, the pressure dependences of both the glass temperature and fragility for the two materials are very close. The fragility is a decreasing function of pressure, although there is no concomitant narrowing of the relaxation peak. The pressure dependence of the relaxation times could be described as a simple volume-activated process, with the activation volume at the glass transition having the same magnitude as the molar volume.
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Affiliation(s)
- Riccardo Casalini
- Chemistry Division, Code 6120, Naval Research Laboratory, Washington, DC 20375-5342, USA
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44
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Roland CM, Casalini R. Temperature and Volume Effects on Local Segmental Relaxation in Poly(vinyl acetate). Macromolecules 2003. [DOI: 10.1021/ma025791z] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. M. Roland
- Naval Research Laboratory, Chemistry Division, Code 6120, Washington, D.C. 20375-5342
| | - R. Casalini
- Naval Research Laboratory, Chemistry Division, Code 6120, Washington, D.C. 20375-5342
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45
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Cailliaux A, Alba-Simionesco C, Frick B, Willner L, Goncharenko I. Local structure and glass transition of polybutadiene up to 4 GPa. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 67:010802. [PMID: 12636483 DOI: 10.1103/physreve.67.010802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2002] [Indexed: 05/24/2023]
Abstract
This communication presents a determination of the glass transition of polybutadiene under very high pressure, and raises the problem of the determination of the relative effects of temperature and density on the glass transition, depending on the pressure and temperature conditions. Local structure and slow dynamics were studied, by neutron scattering and calorimetry. To the best of our knowledge in neutron diffraction on soft matter such a high pressure, up to 4 GPa, was achieved.
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Affiliation(s)
- A Cailliaux
- Laboratoire de Chimie Physique, Bâtiment 349, Université Paris-Sud, 91405 Orsay, France
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46
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Hensel-Bielowka S, Ziolo J, Paluch M, Roland CM. The effect of pressure on the structural and secondary relaxations in 1,1′-bis (p-methoxyphenyl) cyclohexane. J Chem Phys 2002. [DOI: 10.1063/1.1488593] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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