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Plazek DJ, Ngai KL. Resolving the Sub-Rouse Modes by Creep Compliance Measurements in Poly(methyl- para-tolyl-siloxane). Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. J. Plazek
- Department of Mechanical Engineering and Material Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - K. L. Ngai
- CNR-IPCF, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
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2
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Chai Y, Raegen AN, Zhu S, Forrest JA. Crystallization of low molecular weight atactic polystyrene. SOFT MATTER 2018; 14:6883-6891. [PMID: 30087980 DOI: 10.1039/c8sm00424b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We observe and characterize the crystallization of atactic polystyrenes (PS) of nearly oligomeric Mw using atomic force microscopy. We find that the low Mw polystyrene exhibits observable crystals on the surface. The crystals appear to be a few nm thick and nm to microns wide. These crystals grow at all temperatures less than ∼290 K. Melting of crystals was probed over an extended temperature range, and some fraction of the crystals start to melt at 302 K, but some fraction persist to higher temperatures and do not exhibit complete melting until 343 K. The tacticity of the molecules is tested with NMR spectroscopy and found to be atactic. We suggest that the crystals form due simply to the distribution of isomerism along the molecule which necessarily leaves some fraction of the molecules with uniform stereoregularity. This natural crystallinity may be related to previously observed and not definitively explained gel formation in atactic PS (a-PS), as well as cluster formation. The measurements are compared with the theory by Semenov (Macromolecules, 2009, 42, 6761) and together suggest that such crystallinity is possible over a wide range of polymerization index (N), and is limited only by the vanishingly small volume fractions and sluggish growth.
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Affiliation(s)
- Yu Chai
- Department of Physics & Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
| | - Adam N Raegen
- Department of Physics & Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
| | - Shipei Zhu
- Department of Physics & Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
| | - James A Forrest
- Department of Physics & Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. and Perimeter Institute of Theoretical Physics, Waterloo, Ontario N2L 2Y5, Canada
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3
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Połatyńska A, Tomczyk K, Pochylski M, Meier G, Gapinski J, Banachowicz E, Śliwa T, Patkowski A. Temperature dependent FCS studies using a long working distance objective: Viscosities of supercooled liquids and particle size. J Chem Phys 2018; 146:084506. [PMID: 28249427 DOI: 10.1063/1.4977047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this work, we describe new experimental setups for Fluorescence Correlation Spectroscopy (FCS) where a long working distance objective is used. Using these setups, FCS measurements in a broad temperature range for a small sample volume of about 50 μl can be performed. The use of specially designed cells and a dry long working distance objective was essential for avoiding temperature gradients in the sample. The performance of the new setups and a traditional FCS setup with immersion objectives is compared. The FCS data in combination with the Stokes-Einstein (SE) relation were used to obtain the values of the nanoviscosity of a fluid. We show for selected molecular van der Waals supercooled liquids that despite the fact that in these systems, a characteristic length scale can be defined, the nanoviscosity obtained from FCS is in a very good agreement with the macroscopic (rheometric) viscosity of the sample in a broad temperature range. This result corroborates the applicability of the SE relation to supercooled liquids at temperatures above 1.2 Tg. We also show that the temperature dependent size of thermoresponsive microgel particles can be determined by FCS using the designed cells and a long working distance objective in a broader size range without a need to use the correction procedure since the size correction is proportional to the square of the ratio of the hydrodynamic radius to the confocal volume size.
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Affiliation(s)
- Agnieszka Połatyńska
- Molecular Biophysics Division, Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan, Poland
| | - Karolina Tomczyk
- Institute of Complex Systems, Soft Condensed Matter, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - Mikołaj Pochylski
- Molecular Biophysics Division, Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan, Poland
| | - Gerd Meier
- Institute of Complex Systems, Soft Condensed Matter, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - Jacek Gapinski
- Molecular Biophysics Division, Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan, Poland
| | - Ewa Banachowicz
- Molecular Biophysics Division, Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan, Poland
| | - Tomasz Śliwa
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60965 Poznan, Poland
| | - Adam Patkowski
- Molecular Biophysics Division, Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan, Poland
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4
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Mashita R, Kishimoto H, Inoue R, Koda A, Kadono R, Kanaya T. Dynamics of polybutadiene reinforced with unsaturated carboxylate studied by muon spin relaxation (μSR). POLYMER 2016. [DOI: 10.1016/j.polymer.2016.07.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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5
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Elamin K, Cazzato S, Sjöström J, King SM, Swenson J. Long-Range Diffusion in Xylitol–Water Mixtures. J Phys Chem B 2013; 117:7363-9. [DOI: 10.1021/jp401633g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Khalid Elamin
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Stefano Cazzato
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Johan Sjöström
- SP Technical Research Institute of Sweden, SE-501 15 Borås, Sweden
| | - Stephen M. King
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX Oxfordshire,
United Kingdom
| | - Jan Swenson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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6
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Angell CA, Zhao Z. Fluctuations, clusters, and phase transitions in liquids, solutions, and glasses: from metastable water to phase change memory materials. Faraday Discuss 2013; 167:625-41. [DOI: 10.1039/c3fd00111c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Kaminski K, Kaminska E, Wlodarczyk P, Adrjanowicz K, Wojnarowska Z, Grzybowska K, Paluch M. Dynamics of the slow mode in the family of six-carbon monosaccharides monitored by dielectric spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:365103. [PMID: 21386531 DOI: 10.1088/0953-8984/22/36/365103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Broadband dielectric measurements performed on D-glucose, L-sorbose, D-fructose and D-galactose revealed that, except for the structural relaxation process, one can detect in the liquid phase of these carbohydrates a much slower relaxation mode. Recently we have demonstrated that in D-glucose this relaxation mode might be related to the long range correlation of density fluctuations (LRCDF), also called Fischer clusters (FC). Based on the dielectric data obtained for the four monosaccharides we were able to make a more general conclusion about the characteristic dielectric features of the slow mode in the whole family of carbohydrates. We found out that the timescale separation between structural and considered relaxation reaches up to six decades at the glass transition temperature and the dielectric strength decreases significantly with lowering temperature. Another very interesting feature of the slow process is that it can be described by an almost exponential response function. We have found out that the fragility of the slow process lies within the range m = 44-50. Finally, we have also shown that there is a close link between structural and slow relaxation.
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Affiliation(s)
- K Kaminski
- Institute of Physics, Silesian University, ulica Uniwersytecka 4, 40-007 Katowice, Poland
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Kaminski K, Kaminska E, Adrjanowicz K, Wojnarowska Z, Wlodarczyk P, Grzybowska K, Dulski M, Wrzalik R, Paluch M. Observation of the dynamics of clusters in d-glucose with the use of dielectric spectroscopy. Phys Chem Chem Phys 2010; 12:723-30. [DOI: 10.1039/b916699h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Pozo O, Collin D, Finkelmann H, Rogez D, Martinoty P. Gel-like elasticity in glass-forming side-chain liquid-crystal polymers. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:031801. [PMID: 19905137 DOI: 10.1103/physreve.80.031801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Indexed: 05/28/2023]
Abstract
We study the complex shear modulus G of two side-chain liquid-crystal polymers (SCLCPs), a methoxy-phenylbenzoate substituted polyacrylate (thereafter called PAOCH3 ), and a cyanobiphenyl substituted polyacrylate supplied by Merck (thereafter called LCP105) using a piezoelectric rheometer. Two methods of filling the cell are used: (a) a capillary method, which can be used only at high temperature because of the low value of the viscosity, and (b) the classical one, thereafter called compression method, which consists in placing the sample between the two slides of the cell and to bring them closer. By filling the cell at high temperature either with the compression or the capillary method, we show that the response of both compounds is liquidlike ( G' approximately f2 and G'' approximately f , where f is the frequency) for temperatures higher than a certain temperature T0 and gel-like (G' approximately const, G'' approximately f) below T0. This change in behavior from the conventional flow response to a gel-like response, when approaching the glass transition, is observed for nonsliding conditions and for very weak-imposed shear strains. It can be explained by a percolation-type mechanism of preglassy elastic clusters, which correspond to long-range and long-lived density fluctuations that are frozen at the time scale of the experiment. The sample response is therefore the sum of two contributions: one is due to the flow response of the polymer melt and the other to the elastic response of the network formed by the preglassy elastic clusters. By filling the cell below T0 with the compression method, both compounds exhibit a gel-type behavior by gently bringing closer the slides of the cell and an anomalous low-frequency behavior characterized by G'=const and G''=const by increasing the pressure used to bring closer the slides of the cell. A compression-assisted aggregation of the preglassy elastic clusters can explain both the increase in the low-frequency elastic plateau when the sample thickness is decreased and the anomalous low-frequency behavior. Further evidence for the existence of these elastic clusters is provided by the following results: (a) the nonlinear response of the samples as a function of the strain amplitude, which can be explained by the Payne effect, and (b) the aggregation effects, which can be mimicked by a polydimethylsiloxane melt filled with silica particles, the silica particles playing the role of the preglassy elastic clusters. All these observations show that PAOCH3 is not a macroscopically solidlike material with an unconventional type of elasticity, as claimed by Mendil [Phys. Rev. Lett. 96, 077801 (2006)]. The gel-type behavior observed here on two SCLCPs ( PAOCH3 and LCP105) and previously on some conventional flexible polymers (atactic polystyrene, poly-n-butylacrylate) seems to be a generic effect of the glass transition. The presence of the preglassy elastic clusters questions the widely accepted hypothesis of ergodicity in the supercooled state.
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Affiliation(s)
- O Pozo
- Institut Charles Sadron, UPR 22, 67034 Strasbourg Cedex 2, France
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10
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Affiliation(s)
- A. N. Semenov
- Institut Charles Sadron, CNRS - UPR 22, 23 rue du Loess, BP 84047, 67034 Strasbourg Cedex 2, France
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11
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Kuang Q, Zhang J, Wang Z. Revealing Long-Range Density Fluctuations in Dialkylimidazolium Chloride Ionic Liquids by Dynamic Light Scattering. J Phys Chem B 2007; 111:9858-63. [PMID: 17672491 DOI: 10.1021/jp071733+] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, the structures and dynamics of ionic liquids of 1-allyl-3-methylimidazolium chloride ([AMIM][Cl]) and 1-n-butyl-3-methylimidazolium chloride ([BMIM][Cl]) were studied by dynamic light scattering with polarized and depolarized geometries in the temperature range from 300 to 400 K. The temperature range covered supercooled and liquid states for [BMIM][Cl] and covered the liquid state for [AMIM][Cl]. The results show that for these ionic liquids at all chosen temperatures only one ultraslow relaxation is observed in the polarized component of dynamic light scattering, however, the ultraslow relaxation is not observed in the depolarized component. The ultraslow relaxation exhibited several typical features of the "cluster" mode generally found in glass-forming liquids and polymer melts, such as diffusive, strongly scattering-vector-dependent, and nearly exponential characters, which thus corresponded to long-range density fluctuations. The physical origin for long-range density fluctuations was the existence of heterogeneities with large characteristic length scales in these ionic liquids. It was further considered that molecules of these ionic liquids not only tended to aggregate to form dynamic clusters but also possibly formed dynamic networks in the supercooled state and the heterogeneities could exist even at temperatures higher than the melting points.
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Affiliation(s)
- Qinglin Kuang
- CAS Key Laboratory of Engineering Plastics, Joint Laboratory of Polymer Science and Materials, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080 P. R. China
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12
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Štěpánek P, Tuzar Z, Kadlec P, Kříž J. A Dynamic Light Scattering Study of Fast Relaxations in Polymer Solutions. Macromolecules 2007. [DOI: 10.1021/ma0620518] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- P. Štěpánek
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Z. Tuzar
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - P. Kadlec
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - J. Kříž
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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13
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Patkowski A, Gapinski J, Pakula T, Meier G. Physical nature of complex structural relaxation in polysiloxane – PMpTS: α and α′ relaxations. POLYMER 2006. [DOI: 10.1016/j.polymer.2006.05.065] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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14
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Yomogida Y, Minoguchi A, Nozaki R. Ultraslow dielectric relaxation process in supercooled polyhydric alcohols. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 73:041510. [PMID: 16711812 DOI: 10.1103/physreve.73.041510] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 02/27/2006] [Indexed: 05/09/2023]
Abstract
Complex permittivity was obtained on glycerol, xylitol, sorbitol and sorbitol-xylitol mixtures in the supercooled liquid state in the frequency range between 10 microHz and 500 MHz at temperatures near and above the glass transition temperature. For all the materials, a dielectric relaxation process was observed in addition to the well-known structural alpha and Johari-Goldstein beta relaxation process [G. P. Johari and M. Goldstein, J. Chem. Phys. 53, 2372 (1970)]. The relaxation time for the new process is always larger than that for the alpha process. The relaxation time shows non-Arrhenius temperature dependence with correlation to the behavior of the alpha process and it depends on the molecular size systematically. The dielectric relaxation strength for the new process shows the effect of thermal history and decreases exponentially with time at a constant temperature. It can be considered that a nonequilibrium dynamics causes the new process.
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Affiliation(s)
- Yoshiki Yomogida
- Division of Physics, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan
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15
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Kriegs H, Gapinski J, Meier G, Paluch M, Pawlus S, Patkowski A. Pressure effects on the α and α′ relaxations in polymethylphenylsiloxane. J Chem Phys 2006; 124:104901. [PMID: 16542098 DOI: 10.1063/1.2177242] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In some polymers, in addition to the usual structural alpha relaxation, a slower alpha' relaxation is observed with a non-Arrhenius temperature dependence. In order to understand better the molecular origin of this alpha' relaxation in poly(methylphenylsiloxane) (PMPS) we have studied, for the first time, the pressure dependence of its relaxation time, together with the usual temperature dependence, by means of dynamic light scattering (DLS). For the same material the alpha relaxation was also studied by means of DLS and dielectric spectroscopy (DS) in broad temperature and pressure ranges. We find that the temperature dependence of both alpha and alpha' relaxation times, at all pressures studied, can be described by a double Vogel-Fulcher-Tammann (VFT) law. The pressure dependence of the characteristic temperatures Tg (glass transition temperature) and T0 (Vogel temperature) as well as the activation volumes for both alpha and alpha' processes are very similar, indicating, that both relaxation processes originate from similar local molecular dynamics. Additionally, for both alpha and alpha' relaxations the combined temperature and pressure dependences of the relaxation times can be described using a parameter Gamma=rhon/T with the same value of the exponent n.
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Affiliation(s)
- H Kriegs
- Forschungszentrum Jülich, Institut für Festkörperforschung, Weiche Materie, D-52425 Jülich, Germany.
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Collin D, Martinoty P. Commentary on "Solid-like rheological response of non-entangled polymers in the molten state" by H. Mendil et al. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2006; 19:87-98; discussion 99-100. [PMID: 16416250 DOI: 10.1140/epje/e2006-00005-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Indexed: 05/06/2023]
Abstract
We discuss the rheology experiments on classical and liquid crystal polymer melts by Mendil et al., in the light of the old and new piezorheometry experiments we have carried out on both types of melt. The mechanical behavior we have observed in the linear and non-linear regimes are independent of the melt studied (classical or liquid crystal), and of their nature (siloxane-type, acrylate-type and styrene-type). In the linear regime, the mechanical behavior of the melts presents two components: the first one is the conventional contribution. It is due to polymer chains, and is independent of sample thickness. The second one, which can be observed only when a strong interaction between the compound and the substrate exists, is associated with the glass transition. This component displays an elastic response depending on the sample thickness, and disappears at high temperature. It can be explained by assuming the presence of long-range density fluctuations, which are associated with the glass transition, and frozen at the frequencies used in the experiments. The experiments as a function of the applied strain show that the value of the elastic component decreases when the applied strain increases. This slipping transition occurs progressively, which highlights the heterogeneous nature of the anchoring. The results on the classical polymer by Mendil et al. can be considered to be consistent with ours. In contrast, their results on the liquid crystal polymer differ markedly from ours, showing that the elastic response of this sample has not the same origin.
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Affiliation(s)
- D Collin
- Institut de Mécanique des Fluides et des Solides, UMR 7507 CNRS-ULP, 67000, Strasbourg, France
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17
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Sills S, Gray T, Overney RM. Molecular dissipation phenomena of nanoscopic friction in the heterogeneous relaxation regime of a glass former. J Chem Phys 2005; 123:134902. [PMID: 16223326 DOI: 10.1063/1.2038907] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Nanoscale sliding friction involving a polystyrene melt near its glass transition temperature Tg (373 K) exhibited dissipation phenomena that provide insight into the underlying molecular relaxation processes. A dissipative length scale that shows significant parallelism with the size of cooperatively rearranging regions (CRRs) could be experimentally deduced from friction-velocity isotherms, combined with dielectric loss analysis. Upon cooling to approximately 10 K above Tg, the dissipation length Xd grew from a segmental scale of approximately 3 A to 2.1 nm, following a power-law relationship with the reduced temperature Xd approximately TR-phi. The resulting phi=1.89+/-0.08 is consistent with growth predictions for the length scale of CRRs in the heterogeneous regime of fragile glass formers. Deviations from the power-law behavior closer to Tg suggest that long-range processes, e.g., the normal mode or ultraslow Fischer modes, may couple with the alpha relaxation, leading to energy dissipation in domains of tens of nanometers.
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Affiliation(s)
- Scott Sills
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195-1750, USA
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18
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Bakai AS, Fischer EW. Nature of long-range correlations of density fluctuations in glass-forming liquids. J Chem Phys 2004; 120:5235-52. [PMID: 15267395 DOI: 10.1063/1.1648300] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Based on a concise review of the experimental data, a theory of the structural, kinetic, and dynamic features of the Fischer cluster is put forward. This theory is based on the idea of heterophase fluctuations of glass-forming liquids. According to these ideas in a one-component liquid the solidlike and fluidlike transient associations of molecules (fluctuons) are formed. The fluctuons differ in the short-range order and, consequently, in the free energy. They form a random free energy landscape. The random field free energy functional of the Ginzburg-Landau type, which accounts for the free energy landscape, is deduced. Based on this, the phase equilibrium, critical behavior, and ordering phenomena of the heterophase liquid are considered. It is shown that in the critical region an effective attractive interaction of the fluctuons results in their gravitation and formation of correlated fractal aggregations. The aggregation consists of the fluctuons of similar short-range order. The fractal aggregation formation is a special structural state of the liquid above the glass transition temperature. The condition at which the aggregations are formed is formulated. Thus it is shown that the Fischer cluster is an array of fractal aggregations of fluctuons. The growth kinetics and dynamics of the Fischer cluster are described. The experimental data are analyzed and discussed using the theory that is put forward.
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Affiliation(s)
- A S Bakai
- National Science Center Kharkiv, Institute of Physics and Technology, 61108 Kharkiv, Ukraine
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19
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Eckstein E, Qian J, Hentschke R, Thurn-Albrecht T, Steffen W, Fischer EW. X-ray scattering study and molecular simulation of glass forming liquids: Propylene carbonate and salol. J Chem Phys 2000. [DOI: 10.1063/1.1288907] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Patkowski A, Thurn-Albrecht T, Banachowicz E, Steffen W, Bösecke P, Narayanan T, Fischer EW. Long-range density fluctuations in orthoterphenyl as studied by means of ultrasmall-angle x-ray scattering. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 61:6909-13. [PMID: 11088383 DOI: 10.1103/physreve.61.6909] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2000] [Indexed: 11/07/2022]
Abstract
The structure factor of a fragile glass-forming liquid orthoterphenyl was measured in the previously inaccessible intermediate q range between the conventional light scattering (LS) and small-angle x-ray scattering (SAXS) q ranges using the low-angle scattering beam line at the European Synchrotron Radiation Facility. At low q the structure factor exhibits an excess scattering and matches well the LS data. This excess scattering is due to long-range density fluctuations also observed in the isotropic component of scattered light. At high q the structure factor decays to a plateau corresponding to the isothermal compressibility in agreement with the conventional SAXS data. In the intermediate q range, the structure factor exhibits a power law q dependence which indicates that the excess scattering is due to fractal aggregates of denser domains.
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Affiliation(s)
- A Patkowski
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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21
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Matsumiya Y, Watanabe H, Inoue T, Osaki K, Yao ML. Rheo-Dielectric Behavior of Oligostyrene and Polyisoprene. Macromolecules 1998. [DOI: 10.1021/ma980465y] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Y. Matsumiya
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611, Japan
| | - H. Watanabe
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611, Japan
| | - T. Inoue
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611, Japan
| | - K. Osaki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611, Japan
| | - M.-L. Yao
- Rheometric Scientific, F. E., 2-19-6 Yanagibashi, Taito-ku, Tokyo 111, Japan
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