1
|
Zhang X, Wei W, Xiong H. Hierarchical Dynamics of Nonsticky Molecular Nanoparticle-Tethered Polymers: End and Topology Effects. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
2
|
Kim HS, Kwon T, Park CB, Sung BJ. Temperature Dependence of Conformational Relaxation of Poly(ethylene oxide) Melts. Polymers (Basel) 2021; 13:4049. [PMID: 34833348 PMCID: PMC8618988 DOI: 10.3390/polym13224049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/12/2021] [Accepted: 11/18/2021] [Indexed: 11/16/2022] Open
Abstract
The time-temperature superposition (TTS) principle, employed extensively for the analysis of polymer dynamics, is based on the assumption that the different normal modes of polymer chains would experience identical temperature dependence. We aim to test the critical assumption for TTS principle by investigating poly(ethylene oxide) (PEO) melts, which have been considered excellent solid polyelectrolytes. In this work, we perform all-atom molecular dynamics simulations up to 300 ns at a range of temperatures for PEO melts. We find from our simulations that the conformations of strands of PEO chains in melts show ideal chain statistics when the strand consists of at least 10 monomers. At the temperature range of T= 400 to 300 K, the mean-square displacements (⟨Δr2(t)⟩) of the centers of mass of chains enter the Fickian regime, i.e., ⟨Δr2(t)⟩∼t1. On the other hand, ⟨Δr2(t)⟩ of the monomers of the chains scales as ⟨Δr2(t)⟩∼t1/2 at intermediate time scales as expected for the Rouse model. We investigate various relaxation modes of the polymer chains and their relaxation times (τn), by calculating for each strand of n monomers. Interestingly, different normal modes of the PEO chains experience identical temperature dependence, thus indicating that the TTS principle would hold for the given temperature range.
Collapse
Affiliation(s)
| | | | | | - Bong June Sung
- Department of Chemistry, Sogang University, Seoul 04107, Korea; (H.S.K.); (T.K.); (C.B.P.)
| |
Collapse
|
3
|
Diogo HP, Moura Ramos JJ. New contributions from thermal and dielectric techniques to the understanding of the dynamic properties of medium to long chain poly (propylene glycols). POLYM ENG SCI 2021. [DOI: 10.1002/pen.25687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Hermínio P. Diogo
- CQE–Centro de Química Estrutural, Complexo I, Instituto Superior Técnico Universidade de Lisboa Lisbon Portugal
| | - Joaquim J. Moura Ramos
- CQE–Centro de Química Estrutural, Complexo I, Instituto Superior Técnico Universidade de Lisboa Lisbon Portugal
| |
Collapse
|
4
|
Liu AY, Emamy H, Douglas JF, Starr FW. Effects of Chain Length on the Structure and Dynamics of Semidilute Nanoparticle–Polymer Composites. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02500] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ari Y. Liu
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States
| | - Hamed Emamy
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Jack F. Douglas
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Francis W. Starr
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States
| |
Collapse
|
5
|
Wang YC, Zhang JF, Chiu MH, Li JH, Jui CY, Yang TH, Lee WJ. Molecular-weight and cooling-rate dependence of polymer thermodynamics in molecular dynamics simulation. Polym J 2020. [DOI: 10.1038/s41428-020-00443-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
6
|
Pestryaev EM. Chain Heterogeneity in Simulated Polymer Melts: Segment Orientational Autocorrelation Function. POLYMER SCIENCE SERIES A 2020. [DOI: 10.1134/s0965545x20060085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
7
|
Chremos A, Douglas JF. A comparative study of thermodynamic, conformational, and structural properties of bottlebrush with star and ring polymer melts. J Chem Phys 2018; 149:044904. [DOI: 10.1063/1.5034794] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Alexandros Chremos
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Jack F. Douglas
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| |
Collapse
|
8
|
Pestryaev EM. Oscillating Free Induction Decay in Polymer Systems: Theoretical Analysis. POLYMER SCIENCE SERIES A 2018. [DOI: 10.1134/s0965545x18040090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
9
|
Weißheit S, Kahse M, Kämpf K, Tietze A, Vogel M, Winter R, Thiele CM. Elastin-like Peptide in Confinement: FT-IR and NMR T
1 Relaxation Data. Z PHYS CHEM 2018. [DOI: 10.1515/zpch-2017-1047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
We employed FT-IR and NMR experiments to investigate the influence of a cell-mimicking crowding environment on the structure and dynamics of an elastin-like peptide (ELP) with the sequence GVG(VPGVG)3, which – due to a high number of hydrophobic amino acid side chains – exhibits an inverse temperature transition (ITT). As simplified crowding agent, we used 30 wt% Ficoll. The FT-IR data revealed the well-known broad ITT above ~25°C, as observed by the decrease of the relative population of random coil structures and the concomitant increase of type II β-turns. Interestingly, the addition of Ficoll leads to a destabilizing effect of type II β-turn structures. This is in contrast to the expected excluded-volume effect of the macromolecular crowder, but can be explained by weak interactions of the peptide with the polysaccharide chains of the crowding agent. Further, the crowding agent leads to the onset of a reversal of the folding transition at high temperatures. The full assignment of the ELP allowed for a residue-specific investigation of the dynamic behavior of ELP by NMR. Due to a strong change of microscopic viscosity between native/buffered conditions and crowded conditions, relaxation data remain inconclusive with respect to the observation of an ITT. Hence, no quantitative details in terms of internal conformational changes can be obtained. However, temperature dependent differences in the 13C relaxation behavior between core and terminal parts of the peptide indicate temperature induced changes in the internal dynamics with generally higher internal mobility at chain ends: This is in full agreement with FT-IR data. In harmony with the FT-IR analysis, macromolecular crowding does not lead to significant changes in the relaxation behavior.
Collapse
Affiliation(s)
- Susann Weißheit
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie , Technische Universität Darmstadt, Alarich-Weiss-Str. 16 , 64287 Darmstadt , Germany
| | - Marie Kahse
- Physical Chemistry I – Biophysical Chemistry, Faculty of Chemistry and Chemical Biology , TU Dortmund University, Otto-Hahn-Str. 4a , 44227 Dortmund , Germany
| | - Kerstin Kämpf
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Alesia Tietze
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie , Technische Universität Darmstadt, Alarich-Weiss-Str. 16 , 64287 Darmstadt , Germany
| | - Michael Vogel
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Roland Winter
- Physical Chemistry I – Biophysical Chemistry, Faculty of Chemistry and Chemical Biology , TU Dortmund University, Otto-Hahn-Str. 4a , 44227 Dortmund , Germany
| | - Christina Marie Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie , Technische Universität Darmstadt, Alarich-Weiss-Str. 16 , 64287 Darmstadt , Germany
| |
Collapse
|
10
|
Henritzi P, Bormuth A, Klameth F, Vogel M. A molecular dynamics simulations study on the relations between dynamical heterogeneity, structural relaxation, and self-diffusion in viscous liquids. J Chem Phys 2016; 143:164502. [PMID: 26520522 DOI: 10.1063/1.4933208] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We perform molecular dynamics simulations for viscous liquids to study the relations between dynamical heterogeneity, structural (α) relaxation, and self-diffusion. For atomistic models of supercooled water, polymer melts, and an ionic liquid, we characterize the space-time characteristics of dynamical heterogeneity by the degree of deviations from Gaussian displacement statistics (α2), the size of clusters comprising highly mobile particles (S(w)), and the length of strings consisting of cooperatively moving particles (L(w)). Comparison of our findings with previous simulation results for a large variety of viscous liquids, ranging from monoatomic liquids to silica melt, reveals a nearly universal decoupling between the time scales of maximum non-Gaussian parameter (τ(α2)) and the time constant of the α relaxation (τ(α)) upon cooling, explicitly, τ(α2) ∝τ(α)(3/4). Such uniform relation was not observed between the peak times of S(w) or L(w) and τ(α). On the other hand, the temperature-dependent time scale of maximum string length (τ(L)) follows the inverse of the self-diffusion coefficient (D) for various systems at sufficiently low temperatures, i.e., τ(L) ∝ D(-1). These observations are discussed in view of a breakdown of the Stokes-Einstein relation for the studied systems. It is found that the degree of deviation from this relation is correlated with the stretching of the α relaxation.
Collapse
Affiliation(s)
- Patrick Henritzi
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - André Bormuth
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Felix Klameth
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| |
Collapse
|
11
|
Chremos A, Douglas JF. Communication: When does a branched polymer become a particle? J Chem Phys 2015; 143:111104. [DOI: 10.1063/1.4931483] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
Chremos A, Glynos E, Green PF. Structure and dynamical intra-molecular heterogeneity of star polymer melts above glass transition temperature. J Chem Phys 2015; 142:044901. [DOI: 10.1063/1.4906085] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Alexandros Chremos
- Department of Chemical Engineering, Centre for Process Systems Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Emmanouil Glynos
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Peter F. Green
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| |
Collapse
|
14
|
Diddens D, Heuer A. Chain end mobilities in polymer melts--a computational study. J Chem Phys 2015; 142:014906. [PMID: 25573582 DOI: 10.1063/1.4905238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Rouse model can be regarded as the standard model to describe the dynamics of a short polymer chain under melt conditions. In this contribution, we explicitly check one of the fundamental assumptions of this model, namely, that of a uniform friction coefficient for all monomers, on the basis of MD simulation data of a poly(ethylene oxide) (PEO) melt. This question immediately arises from the fact that in a real polymer melt, the terminal monomers have on average more intermolecular neighbors than the central monomers, and one would expect that exactly these details affect the precise value of the friction coefficient. The mobilities are determined by our recently developed statistical method, which provides detailed insights into the local polymer dynamics. Moreover, it yields complementary information to that obtained from the mean square displacement (MSD) or the Rouse mode analysis. It turns out that the Rouse assumption of a uniform mobility is fulfilled to a good approximation for the PEO melt. However, a more detailed analysis reveals that the underlying microscopic dynamics are highly affected by different contributions from intra- and intermolecular excluded volume interactions, which cannot be taken into account by a modified friction coefficient. Minor deviations occur only for the terminal monomers on larger time scales, which can be attributed to the presence of two different escape mechanisms from their first coordination sphere. These effects remain elusive when studying the dynamics with the MSD only.
Collapse
Affiliation(s)
- Diddo Diddens
- Institute of Physical Chemistry, University of Münster, Corrensstrasse 28/30, 48149 Münster, Germany
| | - Andreas Heuer
- Institute of Physical Chemistry, University of Münster, Corrensstrasse 28/30, 48149 Münster, Germany
| |
Collapse
|
15
|
Klameth F, Henritzi P, Vogel M. Static and dynamic length scales in supercooled liquids: Insights from molecular dynamics simulations of water and tri-propylene oxide. J Chem Phys 2014; 140:144501. [DOI: 10.1063/1.4870089] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
|
16
|
Miwa Y, Udagawa T, Urakawa O, Nobukawa S, Kutsumizu S. Rapid Stretching Vibration at the Polymer Chain End. ACS Macro Lett 2014; 3:126-129. [PMID: 35590491 DOI: 10.1021/mz400628b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Stretching vibrations of aliphatic C-D bonds at the chain end and midchain site of partially deuterated polystyrene (PS) were determined by Fourier transform infrared (FT-IR) spectroscopy. It was first found that the stretching vibration at the chain end is more rapid compared to that at the midchain site in the glassy bulk state. The difference in the frequencies of the stretching vibrations at the chain end and midchain site changed little even when the PS was dissolved in toluene. Moreover, the DFT vibrational frequency calculations showed that the C-D bonds at the end site intrinsically have higher vibrational frequency because of lower intramolecular interactions at the chain end. From these results, it was concluded that the main origin for the local rapid stretching vibration at the chain end is not intermolecular effects but reduced intramolecular interactions induced by the discontinuity of the repeating unit at the chain end.
Collapse
Affiliation(s)
- Yohei Miwa
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
| | - Taro Udagawa
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
| | - Osamu Urakawa
- Department
of Macromolecular Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Shogo Nobukawa
- School
of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Shoichi Kutsumizu
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
| |
Collapse
|
17
|
Chremos A, Nikoubashman A, Panagiotopoulos AZ. Flory-Huggins parameter χ, from binary mixtures of Lennard-Jones particles to block copolymer melts. J Chem Phys 2014; 140:054909. [DOI: 10.1063/1.4863331] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
18
|
Bormuth A, Hofmann M, Henritzi P, Vogel M, Rössler EA. Chain-Length Dependence of Polymer Dynamics: A Comparison of Results from Molecular Dynamics Simulations and Field-Cycling 1H NMR. Macromolecules 2013. [DOI: 10.1021/ma401198c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- André Bormuth
- Institut
für Festkörperphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - Marius Hofmann
- Experimentalphysik
II, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Patrick Henritzi
- Institut
für Festkörperphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - Michael Vogel
- Institut
für Festkörperphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - Ernst A. Rössler
- Experimentalphysik
II, Universität Bayreuth, D-95440 Bayreuth, Germany
| |
Collapse
|
19
|
Henritzi P, Bormuth A, Vogel M. Interpretation of 1H and 2H spin-lattice relaxation dispersions: insights from molecular dynamics simulations of polymer melts. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2013; 54:32-40. [PMID: 23830720 DOI: 10.1016/j.ssnmr.2013.06.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 06/05/2013] [Accepted: 06/08/2013] [Indexed: 06/02/2023]
Abstract
We demonstrate that molecular dynamics simulations are a versatile tool to ascertain the interpretation of spin-lattice relaxation data. For (1)H, our simulation approach allows us to separate and to compare intra- and inter-molecular contributions to spin-lattice relaxation dispersions. Dealing with the important example of polymer melts, we show that the intramolecular parts of (1)H spectral densities and correlation functions are governed by rotational motion, while their inter-molecular counterparts provide access to translational motion, in particular, to mean-squared displacements and self-diffusion coefficients. Exploiting that the full microscopic information is available from molecular dynamics simulations, we determine the range of validity of experimental approaches, which often assume Gaussian dynamics, and we provide guidelines for the determination of free parameters required in experimental analyses. For (2)H, we examine the traditional methodology to extract correlation times of complex dynamics from relaxation data. Furthermore, based on knowledge from our computational study, it is shown that measurement of (2)H spin-lattice relaxation dispersions allows one to disentangle the intra- and inter-molecular contributions to the corresponding (1)H data in experimental work. Altogether, our simulation results yield a solid basis for future (1)H and (2)H spin-lattice relaxation analysis.
Collapse
Affiliation(s)
- Patrick Henritzi
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | | | | |
Collapse
|
20
|
Hezaveh S, Samanta S, Milano G, Roccatano D. Molecular dynamics simulation study of solvent effects on conformation and dynamics of polyethylene oxide and polypropylene oxide chains in water and in common organic solvents. J Chem Phys 2012; 136:124901. [DOI: 10.1063/1.3694736] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|