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Phillies GDJ. Simulational Tests of the Rouse Model. Polymers (Basel) 2023; 15:2615. [PMID: 37376261 DOI: 10.3390/polym15122615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 05/24/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
An extensive review of literature simulations of quiescent polymer melts is given, considering results that test aspects of the Rouse model in the melt. We focus on Rouse model predictions for the mean-square amplitudes ⟨(Xp(0))2⟩ and time correlation functions ⟨Xp(0)Xp(t)⟩ of the Rouse mode Xp(t). The simulations conclusively demonstrate that the Rouse model is invalid in polymer melts. In particular, and contrary to the Rouse model, (i) mean-square Rouse mode amplitudes ⟨(Xp(0))2⟩ do not scale as sin-2(pπ/2N), N being the number of beads in the polymer. For small p (say, p≤3) ⟨(Xp(0))2⟩ scales with p as p-2; for larger p, it scales as p-3. (ii) Rouse mode time correlation functions ⟨Xp(t)Xp(0)⟩ do not decay with time as exponentials; they instead decay as stretched exponentials exp(-αtβ). β depends on p, typically with a minimum near N/2 or N/4. (iii) Polymer bead displacements are not described by independent Gaussian random processes. (iv) For p≠q, ⟨Xp(t)Xq(0)⟩ is sometimes non-zero. (v) The response of a polymer coil to a shear flow is a rotation, not the affine deformation predicted by Rouse. We also briefly consider the Kirkwood-Riseman polymer model.
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2
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Hong Z, Feng L, Watanabe H, Chen Q, Guo H. End-to-End Fluctuation of cis-Poly(isoprene) under Constraints from Slow Poly( tert-butyl styrene). Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c00999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Affiliation(s)
- Zonghao Hong
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- University of Science and Technology of China, Hefei 230026, China
| | - Lukun Feng
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hiroshi Watanabe
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Quan Chen
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- University of Science and Technology of China, Hefei 230026, China
| | - Hongxia Guo
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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Martínez-Tong DE, Ochs J, Barroso-Bujans F, Alegria A. Broadband dielectric spectroscopy to validate architectural features in Type-A polymers: Revisiting the poly(glycidyl phenyl ether) case. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2019; 42:93. [PMID: 31317340 DOI: 10.1140/epje/i2019-11859-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 06/24/2019] [Indexed: 06/10/2023]
Abstract
Broadband dielectric spectroscopy (BDS) is a powerful technique that allows studying the molecular dynamics of materials containing polar entities. Among a vast set of different applications, BDS can be used as a complementary tool in polymer synthesis. In this work, we will show how BDS can be used to validate architectural features in Type-A polymers, those having a net dipole moment component along the chain contour. Specifically, we will focus on the evaluation of the dielectric relaxation of poly(glycidyl phenyl ether) (PGPE) samples designed and synthesized with a variety of topologies and regio-orders: linear regio-regular chains synthesized from monofunctional and bifunctional initiators, macrocyclic regio-regular chains, and linear and macrocyclic regio-irregular chains. Our study highlights the impact of using BDS as a complementary characterization technique for providing topological details of polymers, which are otherwise not possible with many traditional techniques (e.g., NMR and mass spectrometry).
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Affiliation(s)
- Daniel E Martínez-Tong
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018, San Sebastian, Spain.
- Donostia International Physics Center (DIPC), Paseo Manuel Lardizábal 4, 20018, San Sebastian, Spain.
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080, San Sebastian, Spain.
| | - Jordan Ochs
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018, San Sebastian, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel Lardizábal 4, 20018, San Sebastian, Spain
| | - Fabienne Barroso-Bujans
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018, San Sebastian, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel Lardizábal 4, 20018, San Sebastian, Spain
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080, San Sebastian, Spain
- IKERBASQUE - Basque Foundation for Science, María Díaz de Haro 3, E-48013, Bilbao, Spain
| | - Angel Alegria
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018, San Sebastian, Spain
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080, San Sebastian, Spain
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Ochs J, Martínez-Tong DE, Alegria A, Barroso-Bujans F. Dielectric Relaxation as a Probe To Verify the Symmetrical Growth of Two-Arm Poly(glycidyl phenyl ether) Initiated by t-BuP 4/Ethylene Glycol. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02530] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jordan Ochs
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, San Sebastian 20018, Spain
- Donostia International
Physics Center (DIPC), Paseo Manuel Lardizábal 4, San Sebastian 20018, Spain
| | - Daniel E. Martínez-Tong
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, San Sebastian 20018, Spain
- Donostia International
Physics Center (DIPC), Paseo Manuel Lardizábal 4, San Sebastian 20018, Spain
| | - Angel Alegria
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, San Sebastian 20018, Spain
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, San Sebastian 20080, Spain
| | - Fabienne Barroso-Bujans
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, San Sebastian 20018, Spain
- Donostia International
Physics Center (DIPC), Paseo Manuel Lardizábal 4, San Sebastian 20018, Spain
- IKERBASQUE - Basque
Foundation for Science, María Díaz de Haro 3, E-48013 Bilbao, Spain
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5
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Arrese-Igor S, Alegría A, Colmenero J. On the non-exponentiality of the dielectric Debye-like relaxation of monoalcohols. J Chem Phys 2017; 146:114502. [DOI: 10.1063/1.4978585] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- S. Arrese-Igor
- Centro de Física de Materiales (CSIC-UPV/EHU), Materials Physics Center (MPC), Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain
| | - A. Alegría
- Centro de Física de Materiales (CSIC-UPV/EHU), Materials Physics Center (MPC), Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain
- Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - J. Colmenero
- Centro de Física de Materiales (CSIC-UPV/EHU), Materials Physics Center (MPC), Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain
- Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
- Donostia International Physics Center DIPC, Paseo Manuel Lardizabal 4, 20018 San Sebastián, Spain
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6
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Napolitano S, Glynos E, Tito NB. Glass transition of polymers in bulk, confined geometries, and near interfaces. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2017; 80:036602. [PMID: 28134134 DOI: 10.1088/1361-6633/aa5284] [Citation(s) in RCA: 247] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
When cooled or pressurized, polymer melts exhibit a tremendous reduction in molecular mobility. If the process is performed at a constant rate, the structural relaxation time of the liquid eventually exceeds the time allowed for equilibration. This brings the system out of equilibrium, and the liquid is operationally defined as a glass-a solid lacking long-range order. Despite almost 100 years of research on the (liquid/)glass transition, it is not yet clear which molecular mechanisms are responsible for the unique slow-down in molecular dynamics. In this review, we first introduce the reader to experimental methodologies, theories, and simulations of glassy polymer dynamics and vitrification. We then analyse the impact of connectivity, structure, and chain environment on molecular motion at the length scale of a few monomers, as well as how macromolecular architecture affects the glass transition of non-linear polymers. We then discuss a revised picture of nanoconfinement, going beyond a simple picture based on interfacial interactions and surface/volume ratio. Analysis of a large body of experimental evidence, results from molecular simulations, and predictions from theory supports, instead, a more complex framework where other parameters are relevant. We focus discussion specifically on local order, free volume, irreversible chain adsorption, the Debye-Waller factor of confined and confining media, chain rigidity, and the absolute value of the vitrification temperature. We end by highlighting the molecular origin of distributions in relaxation times and glass transition temperatures which exceed, by far, the size of a chain. Fast relaxation modes, almost universally present at the free surface between polymer and air, are also remarked upon. These modes relax at rates far larger than those characteristic of glassy dynamics in bulk. We speculate on how these may be a signature of unique relaxation processes occurring in confined or heterogeneous polymeric systems.
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Affiliation(s)
- Simone Napolitano
- Laboratory of Polymer and Soft Matter Dynamics, Faculté des Sciences, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, 1050 Brussels, Belgium
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7
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Cerveny S, Combarro-Palacios I, Swenson J. Evidence of Coupling between the Motions of Water and Peptides. J Phys Chem Lett 2016; 7:4093-4098. [PMID: 27683955 DOI: 10.1021/acs.jpclett.6b01864] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Studies of protein dynamics at low temperatures are generally performed on hydrated powders and not in biologically realistic solutions of water because of water crystallization. However, here we avoid the problem of crystallization by reducing the size of the biomolecules. We have studied oligomers of the amino acid l-lysine, fully dissolved in water, and our dielectric relaxation data show that the glass transition-related dynamics of the oligomers is determined by the water dynamics, in a way similar to that previously observed for solvated proteins. This implies that the crucial role of water for protein dynamics can be extended to other types of macromolecular systems, where water is also able to determine their conformational fluctuations. Using the energy landscape picture of macromolecules, the thermodynamic criterion for such solvent-slaved macromolecular motions may be that the macromolecules need the entropy contribution from the solvent to overcome the enthalpy barriers between different conformational substates.
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Affiliation(s)
- Silvina Cerveny
- Centro de Fisica de Materiales (CSIC, UPV/EHU)-Materials Physics Center (MPC) , Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Donostia International Physics Center, 20018 San Sebastián, Spain
| | - Izaskun Combarro-Palacios
- Centro de Fisica de Materiales (CSIC, UPV/EHU)-Materials Physics Center (MPC) , Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
| | - Jan Swenson
- Department of Applied Physics, Chalmers University of Technology , SE-412 96 Göteborg, Sweden
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8
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The slow relaxation dynamics in active pharmaceutical ingredients studied by DSC and TSDC: Voriconazole, miconazole and itraconazole. Int J Pharm 2016; 501:39-48. [DOI: 10.1016/j.ijpharm.2016.01.057] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 01/21/2016] [Accepted: 01/22/2016] [Indexed: 11/19/2022]
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9
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Gambino T, Martínez de Ilarduya A, Alegría A, Barroso-Bujans F. Dielectric Relaxations in Poly(glycidyl phenyl ether): Effects of Microstructure and Cyclic Topology. Macromolecules 2016. [DOI: 10.1021/acs.macromol.5b02687] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Thomas Gambino
- Materials
Physics Center, Centro de Física de Materiales (CSIC, UPV/EHU), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
| | - Antxon Martínez de Ilarduya
- Departament
d’Enginyeria Química, Universitat Politècnica de Catalunya, ETSEIB, Diagonal 647, 08028 Barcelona, Spain
| | - Angel Alegría
- Materials
Physics Center, Centro de Física de Materiales (CSIC, UPV/EHU), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Departamento
de Física de Materiales, Universidad del País Vasco (UPV/EHU). Paseo Manuel de Lardizabal 3, E-20018 San Sebastián, Spain
| | - Fabienne Barroso-Bujans
- Materials
Physics Center, Centro de Física de Materiales (CSIC, UPV/EHU), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Donostia International
Physics Center (DIPC), Paseo Manuel
de Lardizabal 4, E-20018 San Sebastián, Spain
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10
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Laredo E, Newman D, Pezzoli R, Müller AJ, Bello A. A complete TSDC description of molecular mobilities in polylactide/starch blends from local to normal modes: Effect of composition, moisture, and crystallinity. ACTA ACUST UNITED AC 2015. [DOI: 10.1002/polb.23963] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Estrella Laredo
- Departamento De Física; Universidad Simón Bolívar; Apartado 89000 Caracas 1080-a Venezuela
| | - Dinorah Newman
- Departamento De Física; Universidad Simón Bolívar; Apartado 89000 Caracas 1080-a Venezuela
| | - Romina Pezzoli
- Departamento De Física; Universidad Simón Bolívar; Apartado 89000 Caracas 1080-a Venezuela
| | - Alejandro J. Müller
- Grupo De Polímeros USB, Departamento De Ciencia De Los Materiales; Universidad Simón Bolívar; Apartado 89000 Caracas 1080-a Venezuela
| | - Alfredo Bello
- Departamento De Física; Universidad Simón Bolívar; Apartado 89000 Caracas 1080-a Venezuela
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11
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Colmenero J. The universal trend of the non-exponential Rouse mode relaxation in polymer systems: a theoretical interpretation based on a generalized Langevin equation. SOFT MATTER 2015; 11:5614-5618. [PMID: 26091238 DOI: 10.1039/c5sm00790a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We show that the universal behavior of the Rouse-mode relaxation in polymer systems - which has been recently reported from experimental data [S. Arrese-Igor, et al., Phys. Rev. Lett., 2014, 113, 078302] - can be quantitatively explained in the framework of a theoretical approach based on: (i) a generalized Langevin equation formalism and (ii) a memory function which takes into account the coupling between intra-chain dynamics and collective dynamics. This approach opens the way for generalizing the magnitudes probing chain dynamics in polymer systems.
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Affiliation(s)
- J Colmenero
- Centro de Física de Materiales (CSIC-UPV/EHU), Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain.
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12
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Arrese-Igor S, Alegría A, Colmenero J. Dielectric relaxation of 2-ethyl-1-hexanol around the glass transition by thermally stimulated depolarization currents. J Chem Phys 2015; 142:214504. [PMID: 26049505 DOI: 10.1063/1.4921655] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We explore new routes for characterizing the Debye-like and α relaxation in 2-ethyl-1-hexanol (2E1H) monoalcohol by using low frequency dielectric techniques including thermally stimulated depolarization current (TSDC) techniques and isothermal depolarization current methods. In this way, we have improved the resolution of the overlapped processes making it possible the analysis of the data in terms of a mode composition as expected for a chain-like response. Furthermore the explored ultralow frequencies enabled to study dynamics at relatively low temperatures close to the glass transition (Tg). Results show, on the one hand, that Debye-like and α relaxation timescales dramatically approach to each other upon decreasing temperature to Tg. On the other hand, the analysis of partial polarization TSDC data confirms the single exponential character of the Debye-like relaxation in 2E1H and rules out the presence of Rouse type modes in the scenario of a chain-like response. Finally, on crossing the glass transition, the Debye-like relaxation shows non-equilibrium effects which are further emphasized by aging treatment and would presumably emerge as a result of the arrest of the structural relaxation below Tg.
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Affiliation(s)
- S Arrese-Igor
- Centro de de Física de Materiales (MPC), Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain
| | - A Alegría
- Centro de de Física de Materiales (MPC), Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain
| | - J Colmenero
- Centro de de Física de Materiales (MPC), Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain
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13
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Colmenero J. Are polymers standard glass-forming systems? The role of intramolecular barriers on the glass-transition phenomena of glass-forming polymers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:103101. [PMID: 25634723 DOI: 10.1088/0953-8984/27/10/103101] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Traditionally, polymer melts have been considered archetypal glass-formers. This has been mainly due to the fact that these systems can easily be obtained as glasses by cooling from the melt, even at low cooling rates. However, the macromolecules, i.e. the structural units of polymer systems in general, are rather different from the standard molecules. They are long objects ('chains') made by repetition of a given chemical motif (monomer) and have intra-macromolecular barriers that limit their flexibility. The influence of these properties on, for instance, the glass-transition temperature of polymers, is a topic that has been widely studied by the polymer community almost from the early times of polymer science. However, in the framework of the glass-community, the relevant influence of intra-macromolecular barriers and chain connectivity on glass-transition phenomena of polymers has started to be recognized only recently. The aim of this review is to give an overview and to critically revise the results reported on this topic over the last years. From these results, it seems to be evident that there are two different mechanisms involved in the dynamic arrest in glass-forming polymers: (i) the intermolecular packing effects, which dominate the dynamic arrest of low molecular weight glass-forming systems; and (ii) the effect of intra-macromolecular barriers combined with chain connectivity. It has also been shown that the mode coupling theory (MCT) is a suitable theoretical framework to discuss these questions. The values found for polymers for the central MCT parameter--the so-called λ-exponent--are of the order of 0.9, clearly higher than the standard values (λ ≈ 0.7) found in systems where the dynamic arrest is mainly driven by packing effects ('standard' glass-formers). Within the MCT, this is a signature of the presence of two competing mechanisms of dynamic arrest, as it has been observed in short-ranged attractive colloids or two component mixtures with dynamic asymmetry. Moreover, recent MD-simulations of a 'bead-spring' polymer model, but including intra-macromolecular potential of different strengths, confirm that the high λ-values found in polymers are due to the effect of intra-macromolecular barriers. Although there are still open questions, these results allow to conclude that there is a fundamental difference between the nature of the glass transition in polymers and in simple (standard) glass-formers.
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Affiliation(s)
- J Colmenero
- Centro de Física de Materiales (CSIC-UPV/EHU) and Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
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14
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Mora E, Diogo HP, Moura Ramos JJ. The features of the normal mode relaxation as studied by thermally stimulated currents. Eur Polym J 2015. [DOI: 10.1016/j.eurpolymj.2015.01.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Mora E, Brás AR, Pyckhout-Hintzen W, Diogo HP, Moura Ramos JJ. The segmental and chain relaxation modes in high-cis-polyisoprene as studied by thermally stimulated currents. J Chem Phys 2015; 142:044903. [PMID: 25638005 DOI: 10.1063/1.4906542] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The technique of Thermally Stimulated Currents is used to study the slow molecular mobility in a series of poly (1,4-cis-isoprene) samples with different molecular weights, Mw, and low polydispersity. The technique revealed a high resolution power, particularly useful in the study of the lower molecular weight samples where the chain and the segmental relaxations strongly overlap. The dynamic crossover that is reported for the normal mode by varying the molecular weight is clearly revealed by the thermally stimulated depolarization currents results through the temperature location, TMn, of the normal mode peak, the values of the relaxation time at TMn, τ(TMn), and the value of the fragility index of the normal mode, mn. The kinetic features of the glass transition relaxation of polyisoprene have also been determined.
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Affiliation(s)
- Elsa Mora
- CQE-Centro de Química Estrutural, Universidade de Lisboa, Complexo I, IST, 1049-001 Lisboa, Portugal
| | - Ana R Brás
- Jülich Centre for Neutron Science and Institute for Complex Systems, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Wim Pyckhout-Hintzen
- Jülich Centre for Neutron Science and Institute for Complex Systems, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Hermínio P Diogo
- CQE-Centro de Química Estrutural, Universidade de Lisboa, Complexo I, IST, 1049-001 Lisboa, Portugal
| | - Joaquim J Moura Ramos
- CQFM-Centro de Química-Física Molecular and IN-Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
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16
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Arrese-Igor S, Alegría A, Colmenero J. Chain Dynamics on Crossing the Glass Transition: Nonequilibrium Effects and Recovery of the Temperature Dependence of the Structural Relaxation. ACS Macro Lett 2014; 3:1215-1219. [PMID: 35610828 DOI: 10.1021/mz500508t] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
In this paper we report thermally stimulated depolarization current results on the chain and segmental dynamics of two monodisperse polyisoprenes accessing both dynamics at ultralow frequency range and exploring the relationship between segmental and chain time scales when crossing the glass transition. In this range, we have recorded experimental evidence of nonequilibrium effects on the slowest chain mode dynamics. The nonequilibrium effects seem to occur simultaneously for both chain and α-relaxation. Moreover, detailed analysis strongly indicates the recovery of an even T-dependence for the chain and α-relaxation dynamics on crossing glass transition and in the glassy state. The obtained results can be understood taking into account the different temperature dependences of the length scales involved in the segmental and chain relaxations.
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Affiliation(s)
- S. Arrese-Igor
- Centro
de Física de Materiales (MPC), Centro mixto CSIC-UPV/EHU, Paseo
Manuel Lardizabal 5, 20018 San Sebastián, Spain
| | - A. Alegría
- Centro
de Física de Materiales (MPC), Centro mixto CSIC-UPV/EHU, Paseo
Manuel Lardizabal 5, 20018 San Sebastián, Spain
- Departamento
de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - J. Colmenero
- Centro
de Física de Materiales (MPC), Centro mixto CSIC-UPV/EHU, Paseo
Manuel Lardizabal 5, 20018 San Sebastián, Spain
- Departamento
de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
- Donostia International Physics Center, Paseo Manuel Lardizabal 4, 20018 San Sebastián, Spain
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