1
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Cheng S, Kogut D, Zheng J, Patil S, Yang F, Lu W. Dynamics of polylactic acid under ultrafine nanoconfinement: The collective interface effect and the spatial gradient. J Chem Phys 2024; 160:114904. [PMID: 38506298 DOI: 10.1063/5.0189762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/16/2024] [Indexed: 03/21/2024] Open
Abstract
Polymers under nanoconfinement can exhibit large alterations in dynamics from their bulk values due to an interface effect. However, understanding the interface effect remains a challenge, especially in the ultrafine nanoconfinement region. In this work, we prepare new geometries with ultrafine nanoconfinement ∼10nm through controlled distributions of the crystalline phases and the amorphous phases of a model semi-crystalline polymer, i.e., the polylactic acid. The broadband dielectric spectroscopy measurements show that ultrafine nanoconfinement leads to a large elevation in the glass transition temperature and a strong increment in the polymer fragility index. Moreover, new relaxation time profile analyses demonstrate a spatial gradient that can be well described by either a single-exponential decay or a double-exponential decay functional form near the middle of the film with a collective interface effect. However, the dynamics at the 1-2 nm vicinity of the interface exhibit a power-law decay that is different from the single-exponential decay or double-exponential decay functional forms as predicted by theories. Thus, these results call for further investigations of the interface effect on polymer dynamics, especially for interfaces with perturbed chain packing.
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Affiliation(s)
- Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - David Kogut
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Juncheng Zheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Shalin Patil
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Fuming Yang
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan 48824, USA
| | - Weiyi Lu
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan 48824, USA
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2
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Emamverdi F, Huang J, Razavi NM, Bojdys MJ, Foster AB, Budd PM, Böhning M, Schönhals A. Molecular Mobility and Gas Transport Properties of Mixed Matrix Membranes Based on PIM-1 and a Phosphinine Containing Covalent Organic Framework. Macromolecules 2024; 57:1829-1845. [PMID: 38435679 PMCID: PMC10902888 DOI: 10.1021/acs.macromol.3c02419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/25/2024] [Accepted: 01/25/2024] [Indexed: 03/05/2024]
Abstract
Polymers with intrinsic microporosity (PIMs) are gaining attention as gas separation membranes. Nevertheless, they face limitations due to their pronounced physical aging. In this study, a covalent organic framework containing λ5-phosphinine moieties, CPSF-EtO, was incorporated as a nanofiller (concentration range 0-10 wt %) into a PIM-1 matrix forming dense films with a thickness of ca. 100 μm. The aim of the investigation was to investigate possible enhancements of gas transport properties and mitigating effects on physical aging. The incorporation of the nanofiller occurred on an nanoaggregate level with domains up to 100 nm, as observed by T-SEM and confirmed by X-ray scattering. Moreover, the X-ray data show that the structure of the microporous network of the PIM-1 matrix is changed by the nanofiller. As molecular mobility is fundamental for gas transport as well as for physical aging, the study includes dielectric investigations of pure PIM-1 and PIM-1/CPSF-EtO mixed matrix membranes to establish a correlation between the molecular mobility and the gas transport properties. Using the time-lag method, the gas permeability and the permselectivity were determined for N2, O2, CH4, and CO2 for samples with variation in filler content. A significant increase in the permeability of CH4 and CO2 (50% increase compared to pure PIM-1) was observed for a concentration of 5 wt % of the nanofiller. Furthermore, the most pronounced change in the permselectivity was found for the gas pair CO2/N2 at a filler concentration of 7 wt %.
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Affiliation(s)
- Farnaz Emamverdi
- Bundesanstalt
für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
| | - Jieyang Huang
- Department
of Chemistry, Humboldt University, Brook-Taylor Straße 2, Berlin 12489, Germany
| | - Negar Mosane Razavi
- Bundesanstalt
für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
| | - Michael J. Bojdys
- Department
of Chemistry, Humboldt University, Brook-Taylor Straße 2, Berlin 12489, Germany
| | - Andrew B. Foster
- School
of Chemistry, University of Manchester, Manchester M 13 9PL, United Kingdom
| | - Peter M. Budd
- School
of Chemistry, University of Manchester, Manchester M 13 9PL, United Kingdom
| | - Martin Böhning
- Bundesanstalt
für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
| | - Andreas Schönhals
- Bundesanstalt
für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
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3
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Phan AD, Schweizer KS. Effect of the nature of the solid substrate on spatially heterogeneous activated dynamics in glass forming supported films. J Chem Phys 2024; 160:074902. [PMID: 38364012 DOI: 10.1063/5.0188016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Accepted: 01/10/2024] [Indexed: 02/18/2024] Open
Abstract
We extend the force-level elastically collective nonlinear Langevin equation theory to treat the spatial gradients of the alpha relaxation time and glass transition temperature, and the corresponding film-averaged quantities, to the geometrically asymmetric case of finite thickness supported films with variable fluid-substrate coupling. The latter typically nonuniversally slows down motion near the solid-liquid interface as modeled via modification of the surface dynamic free energy caging constraints that are spatially transferred into the film and which compete with the accelerated relaxation gradient induced by the vapor interface. Quantitative applications to the foundational hard sphere fluid and a polymer melt are presented. The strength of the effective fluid-substrate coupling has very large consequences for the dynamical gradients and film-averaged quantities in a film thickness and thermodynamic state dependent manner. The interference of the dynamical gradients of opposite nature emanating from the vapor and solid interfaces is determined, including the conditions for the disappearance of a bulk-like region in the film center. The relative importance of surface-induced modification of local caging vs the generic truncation of the long range collective elastic component of the activation barrier is studied. The conditions for the accuracy and failure of a simple superposition approximation for dynamical gradients in thin films are also determined. The emergence of near substrate dead layers, large gradient effects on film-averaged response functions, and a weak non-monotonic evolution of dynamic gradients in thick and cold films are briefly discussed. The connection of our theoretical results to simulations and experiments is briefly discussed, as is the extension to treat more complex glass-forming systems under nanoconfinement.
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Affiliation(s)
- Anh D Phan
- Faculty of Materials Science and Engineering, Phenikaa University, Hanoi 12116, Vietnam
- Phenikaa Institute for Advanced Study, Phenikaa University, Hanoi 12116, Vietnam
| | - Kenneth S Schweizer
- Departments of Materials Science, Chemistry, Chemical and Biomolecular Engineering and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
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4
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Cheng S, Patil S, Cheng S. Hydrogen Bonding Exchange and Supramolecular Dynamics of Monohydroxy Alcohols. PHYSICAL REVIEW LETTERS 2024; 132:058201. [PMID: 38364139 DOI: 10.1103/physrevlett.132.058201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 01/03/2024] [Indexed: 02/18/2024]
Abstract
We unravel hydrogen bonding dynamics and their relationship with supramolecular relaxations of monohydroxy alcohols (MAs) at intermediate times. The rheological modulus of MAs exhibits Rouse scaling relaxation of G(t)∼t^{-1/2} switching to G(t)∼t^{-1} at time τ_{m} before their terminal time. Meanwhile, dielectric spectroscopy reveals clear signatures of new supramolecular dynamics matching with τ_{m} from rheology. Interestingly, the characteristic time τ_{m} follows an Arrhenius-like temperature dependence over exceptionally wide temperatures and agrees well with the hydrogen bonding exchange time from nuclear magnetic resonance measurements. These observations demonstrate the presence of Rouse modes and active chain swapping of MAs at intermediate times. Moreover, detailed theoretical analyses point out explicitly that the hydrogen bonding exchange truncates the Rouse dynamics of the supramolecular chains and triggers the chain-swapping processes, supporting a recently proposed living polymer model.
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Affiliation(s)
- Shinian Cheng
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Shalin Patil
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
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5
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Prabhune P, Comlek Y, Shandilya A, Sundararaman R, Schadler LS, Brinson LC, Chen W. Design of Polymer Nanodielectrics for Capacitive Energy Storage. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2394. [PMID: 37686902 PMCID: PMC10490420 DOI: 10.3390/nano13172394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/05/2023] [Accepted: 08/10/2023] [Indexed: 09/10/2023]
Abstract
Polymer nanodielectrics present a particularly challenging materials design problem for capacitive energy storage applications like polymer film capacitors. High permittivity and breakdown strength are needed to achieve high energy density and loss must be low. Strategies that increase permittivity tend to decrease the breakdown strength and increase loss. We hypothesize that a parameter space exists for fillers of modest aspect ratio functionalized with charge-trapping molecules that results in an increase in permittivity and breakdown strength simultaneously, while limiting increases in loss. In this work, we explore this parameter space, using physics-based, multiscale 3D dielectric property simulations, mixed-variable machine learning and Bayesian optimization to identify the compositions and morphologies which lead to the optimization of these competing properties. We employ first principle-based calculations for interface trap densities which are further used in breakdown strength calculations. For permittivity and loss calculations, we use continuum scale modelling and finite difference solution of Poisson's equation for steady-state currents. We propose a design framework for optimizing multiple properties by tuning design variables including the microstructure and interface properties. Finally, we employ mixed-variable global sensitivity analysis to understand the complex interplay between four continuous microstructural and two categorical interface choices to extract further physical knowledge on the design of nanodielectrics.
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Affiliation(s)
- Prajakta Prabhune
- Thomas Lord Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708, USA; (P.P.); (L.C.B.)
| | - Yigitcan Comlek
- Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA;
| | - Abhishek Shandilya
- Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA; (A.S.); (R.S.)
| | - Ravishankar Sundararaman
- Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA; (A.S.); (R.S.)
| | - Linda S. Schadler
- College of Engineering and Mathematical Sciences, University of Vermont, Burlington, VT 05405, USA;
| | - Lynda Catherine Brinson
- Thomas Lord Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708, USA; (P.P.); (L.C.B.)
| | - Wei Chen
- Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA;
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6
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Rationalizing the interfacial layer in polymer nanocomposites: Correlation between enthalpy and dielectric relaxation. POLYMER 2023. [DOI: 10.1016/j.polymer.2023.125765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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7
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Sakib N, Koh YP, Simon SL. The absolute heat capacity of polymer grafted nanoparticles using fast scanning calorimetry*. POLYM ENG SCI 2022. [DOI: 10.1002/pen.26078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Nazam Sakib
- Department of Chemical Engineering Texas Tech University Lubbock Texas USA
| | - Yung P. Koh
- Department of Chemical Engineering Texas Tech University Lubbock Texas USA
- Department of Chemical and Biomolecular Engineering North Carolina State University Raleigh North Carolina USA
| | - Sindee L. Simon
- Department of Chemical and Biomolecular Engineering North Carolina State University Raleigh North Carolina USA
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8
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Lindemann N, Schawe JEK, Lacayo-Pineda J. Kinetics of the Glass Transition of Silica-Filled Styrene-Butadiene Rubber: The Effect of Resins. Polymers (Basel) 2022; 14:polym14132626. [PMID: 35808677 PMCID: PMC9269213 DOI: 10.3390/polym14132626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/09/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
Resins are important for enhancing both the processability and performance of rubber. Their efficient utilization requires knowledge about their influence on the dynamic glass transition and their miscibility behavior in the specific rubber compound. The resins investigated, poly-(α-methylstyrene) (AMS) and indene-coumarone (IC), differ in molecular rigidity but have a similar aromaticity degree and glass transition temperature. Transmission electron microscopy (TEM) investigations show an accumulation of IC around the silanized silica in styrene–butadiene rubber (SBR) at high contents, while AMS does not show this effect. This higher affinity between IC and the silica surface leads to an increased compactness of the filler network, as determined by dynamic mechanical analysis (DMA). The influence of the resin content on the glass transition of the rubber compounds is evaluated in the sense of the Gordon–Taylor equation and suggests a rigid amorphous fraction for the accumulated IC. Broadband dielectric spectroscopy (BDS) and fast differential scanning calorimetry (FDSC) are applied for the characterization of the dielectric and thermal relaxations as well as for the corresponding vitrification kinetics. The cooling rate dependence of the vitrification process is combined with the thermal and dielectric relaxation time by one single Vogel–Fulcher–Tammann–Hesse equation, showing an increased fragility of the rubber containing AMS.
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Affiliation(s)
- Niclas Lindemann
- Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Callinstraße 3A, 30167 Hanover, Germany
- Continental Reifen Deutschland GmbH, Jädekamp 30, 30419 Hanover, Germany;
- Correspondence:
| | | | - Jorge Lacayo-Pineda
- Continental Reifen Deutschland GmbH, Jädekamp 30, 30419 Hanover, Germany;
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Callinstraße 9, 30167 Hanover, Germany
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9
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Young WW, Saez JP, Katsumata R. Rationalizing the Composition Dependence of Glass Transition Temperatures in Amorphous Polymer/POSS Composites. ACS Macro Lett 2021; 10:1404-1409. [PMID: 35549020 DOI: 10.1021/acsmacrolett.1c00597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report that the fractions of "bonded" or "unbonded" monomers at a filler interface dictate the composition dependence of the glass transition temperatures (Tg) of polyhedral oligomeric silsesquioxane (POSS)-containing nanocomposites. Tg is arguably the single most important material property; however, predicting Tg in nanocomposites is often challenging because of confounding interfacial effects. To this end, we design a model nanocomposite to systematically study Tg of nanocomposites by leveraging the "all-interfacial" nature of ultrasmall POSS fillers loaded into random copolymers of styrene and 2-vinylpyridine (2VP). The amine-functionalized POSS forms hydrogen bonds only with 2VP, which behaves as a "bonded" monomer. The influence of copolymer composition and POSS loading on the Tg of this model composite is successfully explained by a Fox equation framework. This model also captures the Tg increase of other POSS-based polymer composites and potentially directs the future design of nanocomposite materials with tailored Tg.
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Affiliation(s)
- Walter W. Young
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003 United States
| | - Joseph P. Saez
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003 United States
| | - Reika Katsumata
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003 United States
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10
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Zhang W, Starr FW, Douglas JF. Activation free energy gradient controls interfacial mobility gradient in thin polymer films. J Chem Phys 2021; 155:174901. [PMID: 34742183 DOI: 10.1063/5.0064866] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We examine the mobility gradient in the interfacial region of substrate-supported polymer films using molecular dynamics simulations and interpret these gradients within the string model of glass-formation. No large gradients in the extent of collective motion exist in these simulated films, and an analysis of the mobility gradient on a layer-by-layer basis indicates that the string model provides a quantitative description of the relaxation time gradient. Consequently, the string model indicates that the interfacial mobility gradient derives mainly from a gradient in the high-temperature activation enthalpy ΔH0 and entropy ΔS0 as a function of depth z, an effect that exists even in the high-temperature Arrhenius relaxation regime far above the glass transition temperature. To gain insight into the interfacial mobility gradient, we examined various material properties suggested previously to influence ΔH0 in condensed materials, including density, potential and cohesive energy density, and a local measure of stiffness or u2(z)-3/2, where u2(z) is the average mean squared particle displacement at a caging time (on the order of a ps). We find that changes in local stiffness best correlate with changes in ΔH0(z) and that ΔS0(z) also contributes significantly to the interfacial mobility gradient, so it must not be neglected.
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Affiliation(s)
- Wengang Zhang
- Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Francis W Starr
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
| | - Jack F Douglas
- Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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11
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Sattar MA. Interface Structure and Dynamics in Polymer‐Nanoparticle Hybrids: A Review on Molecular Mechanisms Underlying the Improved Interfaces. ChemistrySelect 2021. [DOI: 10.1002/slct.202100831] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Mohammad Abdul Sattar
- R&D Centre MRF Limited Chennai 600019 India
- Colloid and Interface Chemistry Laboratory Department of Chemistry Indian Institute of Technology Madras Chennai 600036 India
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12
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Ge S, Samanta S, Tress M, Li B, Xing K, Dieudonné-George P, Genix AC, Cao PF, Dadmun M, Sokolov AP. Critical Role of the Interfacial Layer in Associating Polymers with Microphase Separation. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00275] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sirui Ge
- Department of Material Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Subarna Samanta
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Martin Tress
- Peter Debye Institute for Soft Matter Physics, Leipzig University, Leipzig 04103, Germany
| | - Bingrui Li
- The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Kunyue Xing
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | | | - Anne-Caroline Genix
- Laboratoire Charles Coulomb (L2C), Université de Montpellier, CNRS, F-34095 Montpellier, France
| | - Peng-Fei Cao
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Mark Dadmun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Alexei P. Sokolov
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
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13
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You W, Cui W, Yu W. Decoupling hydrodynamic and entanglement effects on the modulus reinforcement of grafted silica filled nanocomposites through Thermal and rheological features. POLYMER 2021. [DOI: 10.1016/j.polymer.2020.123323] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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14
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Demuth D, Reuhl M, Hopfenmüller M, Karabas N, Schoner S, Vogel M. Confinement Effects on Glass-Forming Aqueous Dimethyl Sulfoxide Solutions. Molecules 2020; 25:E4127. [PMID: 32917011 PMCID: PMC7570821 DOI: 10.3390/molecules25184127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/04/2020] [Accepted: 09/05/2020] [Indexed: 11/17/2022] Open
Abstract
Combining broadband dielectric spectroscopy and nuclear magnetic resonance studies, we analyze the reorientation dynamics and the translational diffusion associated with the glassy slowdown of the eutectic aqueous dimethyl sulfoxide solution in nano-sized confinements, explicitly, in silica pores with different diameters and in ficoll and lysozyme matrices at different concentrations. We observe that both rotational and diffusive dynamics are slower and more heterogeneous in the confinements than in the bulk but the degree of these effects depends on the properties of the confinement and differs for the components of the solution. For the hard and the soft matrices, the slowdown and the heterogeneity become more prominent when the size of the confinement is reduced. In addition, the dynamics are more retarded for dimethyl sulfoxide than for water, implying specific guest-host interactions. Moreover, we find that the temperature dependence of the reorientation dynamics and of the translational diffusion differs in severe confinements, indicating a breakdown of the Stokes-Einstein-Debye relation. It is discussed to what extent these confinement effects can be rationalized in the framework of core-shell models, which assume bulk-like and slowed-down motions in central and interfacial confinement regions, respectively.
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Affiliation(s)
| | | | | | | | | | - Michael Vogel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany; (D.D.); (M.R.); (M.H.); (N.K.); (S.S.)
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15
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Kritikos G, Rissanou AN, Harmandaris V, Karatasos K. Bound Layer Polymer Behavior on Graphene and Graphene Oxide Nanosheets. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Georgios Kritikos
- Laboratory of Physical Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Anastassia N. Rissanou
- Institute of Applied and Computational Mathematics, Foundation for Research and Technology - Hellas, Heraklion GR-71110, Greece
| | - Vagelis Harmandaris
- Institute of Applied and Computational Mathematics, Foundation for Research and Technology - Hellas, Heraklion GR-71110, Greece
- Department of Mathematics and Applied Mathematics, University of Crete, Heraklion GR-71110, Greece
- Computation-based Science and Technology Research Center, The Cyprus Institute, Nicosia 2121, Cyprus
| | - Kostas Karatasos
- Laboratory of Physical Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
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16
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Mapesa EU, Street DP, Heres MF, Kilbey SM, Sangoro J. Wetting and Chain Packing across Interfacial Zones Affect Distribution of Relaxations in Polymer and Polymer-Grafted Nanocomposites. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00399] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Emmanuel U. Mapesa
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Dayton P. Street
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Maximilian F. Heres
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - S. Michael Kilbey
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Joshua Sangoro
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
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17
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Bailey EJ, Winey KI. Dynamics of polymer segments, polymer chains, and nanoparticles in polymer nanocomposite melts: A review. Prog Polym Sci 2020. [DOI: 10.1016/j.progpolymsci.2020.101242] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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18
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Popov I, Carroll B, Bocharova V, Genix AC, Cheng S, Khamzin A, Kisliuk A, Sokolov AP. Strong Reduction in Amplitude of the Interfacial Segmental Dynamics in Polymer Nanocomposites. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00496] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Ivan Popov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Bobby Carroll
- Department of Physics, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Vera Bocharova
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Anne-Caroline Genix
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, Montpellier F-34095, France
| | - Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lancing, Michigan 48824, United States
| | - Airat Khamzin
- Institute of Physics, Kazan Federal University, Kremlevskaya Str. 18, Kazan, Tatarstan 420008, Russia
| | - Alexander Kisliuk
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Alexei P. Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
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19
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Phan AD, Schweizer KS. Theory of Spatial Gradients of Relaxation, Vitrification Temperature and Fragility of Glass-Forming Polymer Liquids Near Solid Substrates. ACS Macro Lett 2020; 9:448-453. [PMID: 35648500 DOI: 10.1021/acsmacrolett.0c00006] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We employ a new force-level statistical mechanical theory to predict spatial gradients of the structural relaxation time and Tg of polymer liquids near microscopically rough and smooth hard surfaces and contrast the results with vapor interface systems. Repulsive rough (smooth) surfaces induce large slowing down (modest speeding up) of the relaxation time compared to the bulk. Nevertheless, a remarkable degree of universality of distinctive dynamical behaviors is predicted for different polymer chemistries and all interfaces, including a double exponential form of the alpha time gradient, power law decoupling of the relaxation time from its bulk value with exponential spatial variation of the exponent, exponential spatial gradient of Tg, weak dependence of normalized Tg gradients on vitrification criterion, and near linear growth with cooling of the slowed down layer thickness near a rough hard interface. The results appear consistent with simulations and experiments, and multiple testable predictions are made.
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Affiliation(s)
- Anh D. Phan
- Faculty of Materials Science and Engineering, Phenikaa Institute for Advanced Study, Phenikaa University, Hanoi 12116, Vietnam
- Faculty of Information Technology, Artificial Intelligence Laboratory, Phenikaa University, Hanoi 12116, Vietnam
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20
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Cheng S, Sokolov AP. Correlation between the temperature evolution of the interfacial region and the growing dynamic cooperativity length scale. J Chem Phys 2020; 152:094904. [PMID: 33480747 DOI: 10.1063/1.5143360] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Alexei P. Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
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21
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Yang J, Melton M, Sun R, Yang W, Cheng S. Decoupling the Polymer Dynamics and the Nanoparticle Network Dynamics of Polymer Nanocomposites through Dielectric Spectroscopy and Rheology. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01584] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jie Yang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, Sichuan 610065, People’s Republic of China
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Matthew Melton
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Ruikun Sun
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Wei Yang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, Sichuan 610065, People’s Republic of China
| | - Shiwang Cheng
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
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22
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Schweizer KS, Simmons DS. Progress towards a phenomenological picture and theoretical understanding of glassy dynamics and vitrification near interfaces and under nanoconfinement. J Chem Phys 2019; 151:240901. [PMID: 31893888 DOI: 10.1063/1.5129405] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The nature of alterations to dynamics and vitrification in the nanoscale vicinity of interfaces-commonly referred to as "nanoconfinement" effects on the glass transition-has been an open question for a quarter century. We first analyze experimental and simulation results over the last decade to construct an overall phenomenological picture. Key features include the following: after a metrology- and chemistry-dependent onset, near-interface relaxation times obey a fractional power law decoupling relation with bulk relaxation; relaxation times vary in a double-exponential manner with distance from the interface, with an intrinsic dynamical length scale appearing to saturate at low temperatures; the activation barrier and vitrification temperature Tg approach bulk behavior in a spatially exponential manner; and all these behaviors depend quantitatively on the nature of the interface. We demonstrate that the thickness dependence of film-averaged Tg for individual systems provides a poor basis for discrimination between different theories, and thus we assess their merits based on the above dynamical gradient properties. Entropy-based theories appear to exhibit significant inconsistencies with the phenomenology. Diverse free-volume-motivated theories vary in their agreement with observations, with approaches invoking cooperative motion exhibiting the most promise. The elastically cooperative nonlinear Langevin equation theory appears to capture the largest portion of the phenomenology, although important aspects remain to be addressed. A full theoretical understanding requires improved confrontation with simulations and experiments that probe spatially heterogeneous dynamics within the accessible 1-ps to 1-year time window, minimal use of adjustable parameters, and recognition of the rich quantitative dependence on chemistry and interface.
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Affiliation(s)
- Kenneth S Schweizer
- Departments of Materials Science, Chemistry and Chemical & Biomolecular Engineering, Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - David S Simmons
- Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, Florida 33620, USA
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23
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Oh SM, Abbasi M, Shin TJ, Saalwächter K, Kim SY. Initial Solvent-Driven Nonequilibrium Effect on Structure, Properties, and Dynamics of Polymer Nanocomposites. PHYSICAL REVIEW LETTERS 2019; 123:167801. [PMID: 31702348 DOI: 10.1103/physrevlett.123.167801] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Indexed: 06/10/2023]
Abstract
Unusual structures and dynamic properties found in polymer nanocomposites (PNCs) are often attributed to immobilized (adsorbed) polymers at nanoparticle-polymer interfaces, which are responsible for reducing the intrinsic incompatibility between nanoparticles and polymers in PNCs. Although tremendous effort has been made to characterize the presence of immobilized polymers, a systematic understanding of the structure and dynamics under different processing conditions is still lacking. Here, we report that the initial dispersing solvent, which is not present after producing PNCs, drives these nonequilibrium effects on polymer chain dynamics at interfaces. Employing extensive small-angle scattering, proton NMR spectroscopy, and rheometry experiments, we found that the thickness of the immobilized layer can be dependent on the initial solvent, changing the structure and the properties of the PNC significantly. In addition, we show that the outcome of the initial solvent effect becomes more effective at particle volume fractions where the immobile layers begin to interact.
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Affiliation(s)
- Sol Mi Oh
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil Ulsan 44919, Republic of Korea
| | - Mozhdeh Abbasi
- Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Straβe 7, D-06120 Halle, Germany
| | - Tae Joo Shin
- UNIST Central Research Facilities & School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil Ulsan 44919, Republic of Korea
| | - Kay Saalwächter
- Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Straβe 7, D-06120 Halle, Germany
| | - So Youn Kim
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil Ulsan 44919, Republic of Korea
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24
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Zhang W, Emamy H, Pazmiño Betancourt BA, Vargas-Lara F, Starr FW, Douglas JF. The interfacial zone in thin polymer films and around nanoparticles in polymer nanocomposites. J Chem Phys 2019; 151:124705. [DOI: 10.1063/1.5119269] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Wengang Zhang
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
- Materials Science and Engineering, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Hamed Emamy
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
| | - Beatriz A. Pazmiño Betancourt
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
- Materials Science and Engineering, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Fernando Vargas-Lara
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
- Materials Science and Engineering, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Francis W. Starr
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, USA
| | - Jack F. Douglas
- Materials Science and Engineering, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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25
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Abstract
We review recent neutron scattering work and related results from simulation and complementary techniques focusing on the microscopic dynamics of polymers under confinement. Confinement is either realized in model porous materials or in polymer nanocomposites (PNC). The dynamics of such confined polymers is affected on the local segmental level, the level of entanglements as well as on global levels: (i) at the segmental level the interaction with the surface is of key importance. At locally repulsive surfaces compared to the bulk the segmental dynamics is not altered. Attractive surfaces slow down the segmental dynamics in their neighborhood but do not give rise to dead, glassy layers. (ii) Confinement generally has little effect on the inter-chain entanglements: both for weakly as well as for marginally confined polymers the reptation tube size is not changed. Only for strongly confined polymers disentanglement takes place. Similarly, in PNC at higher NP loading disentanglement phenomena are observed; in addition, at very high loading a transition from polymer caused topological constraints to purely geometrical constraints is observed. (iii) On the more global scale NSE experiments revealed important information on the nature of the interphase between adsorbed layer and bulk polymer. (iv) Polymer grafts at NP mutually confine each other, an effect that is most pronounced for one component NP. (v) Global diffusion of entangled polymers both in weakly and strongly attractive PNC is governed by the ratio of bottle-neck to chain size that characterizes the 'entropic barrier' for global diffusion.
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Affiliation(s)
- Dieter Richter
- Jülich Centre for Neutron Science (JCNS-1) and Institute of Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Jülich, Germany.
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26
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Phan AD, Schweizer KS. Influence of Longer Range Transfer of Vapor Interface Modified Caging Constraints on the Spatially Heterogeneous Dynamics of Glass-Forming Liquids. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00754] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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27
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Wang M, Sheng J, Zhou S, Yang Z, Zhang X. Effect of Free Surface Layer and Interfacial Zone on Glass-Transition Behavior of PMMA/CNT Nanocomposite. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02642] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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28
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Phan AD, Schweizer KS. Theory of the spatial transfer of interface-nucleated changes of dynamical constraints and its consequences in glass-forming films. J Chem Phys 2019; 150:044508. [PMID: 30709240 DOI: 10.1063/1.5079250] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We formulate a new theory for how caging constraints in glass-forming liquids at a surface or interface are modified and then spatially transferred, in a layer-by-layer bootstrapped manner, into the film interior in the context of the dynamic free energy concept of the Nonlinear Langevin Equation (NLE) theory approach. The dynamic free energy at any mean location (cage center) involves contributions from two adjacent layers where confining forces are not the same. At the most fundamental level of the theory, the caging component of the dynamic free energy varies essentially exponentially with distance from the interface, saturating deep enough into the film with a correlation length of modest size and weak sensitivity to the thermodynamic state. This imparts a roughly exponential spatial variation of all the key features of the dynamic free energy required to compute gradients of dynamical quantities including the localization length, jump distance, cage barrier, collective elastic barrier, and alpha relaxation time. The spatial gradients are entirely of dynamical, not structural or thermodynamic, origin. The theory is implemented for the hard sphere fluid and diverse interfaces which can be a vapor, a rough pinned particle solid, a vibrating (softened) pinned particle solid, or a smooth hard wall. Their basic description at the level of the spatially heterogeneous dynamic free energy is identical, with the crucial difference arising from the first layer where dynamical constraints can be weakened, softened, or hardly changed depending on the specific interface. Numerical calculations establish the spatial dependence and fluid volume fraction sensitivity of the key dynamical property gradients for five different model interfaces. A comparison of the theoretical predictions for the dynamic localization length and glassy modulus with simulations and experiments for systems with a vapor interface reveals good agreement. The present advance sets the stage for using the Elastically Collective NLE theory to make quantitative predictions for the alpha relaxation time gradient, decoupling phenomena, Tg gradient, and many film-averaged properties of both model and experimental (colloids, molecules, and polymers) systems with diverse interfaces and chemical makeup.
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Affiliation(s)
- Anh D Phan
- Department of Physics, University of Illinois, Urbana, Illinois 61801, USA
| | - Kenneth S Schweizer
- Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
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29
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Phan AD, Schweizer KS. Elastically Collective Nonlinear Langevin Equation Theory of Glass-Forming Liquids: Transient Localization, Thermodynamic Mapping, and Cooperativity. J Phys Chem B 2018; 122:8451-8461. [DOI: 10.1021/acs.jpcb.8b04975] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Klonos P, Bolbukh Y, Koutsiara C, Zafeiris K, Kalogeri O, Sternik D, Deryło–Marczewska A, Tertykh V, Pissis P. Morphology and molecular dynamics investigation of low molecular weight PDMS adsorbed onto Stöber, fumed, and sol-gel silica nanoparticles. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.06.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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31
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Carroll B, Cheng S, Sokolov AP. Analyzing the Interfacial Layer Properties in Polymer Nanocomposites by Broadband Dielectric Spectroscopy. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00825] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Shiwang Cheng
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Alexei P. Sokolov
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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32
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Mark C, Holderer O, Allgaier J, Hübner E, Pyckhout-Hintzen W, Zamponi M, Radulescu A, Feoktystov A, Monkenbusch M, Jalarvo N, Richter D. Polymer Chain Conformation and Dynamical Confinement in a Model One-Component Nanocomposite. PHYSICAL REVIEW LETTERS 2017; 119:047801. [PMID: 29341730 DOI: 10.1103/physrevlett.119.047801] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Indexed: 06/07/2023]
Abstract
We report a neutron-scattering investigation on the structure and dynamics of a single-component nanocomposite based on SiO_{2} particles that were grafted with polyisoprene chains at the entanglement limit. By skillful labeling, we access both the monomer density in the corona as well as the conformation of the grafted chains. While the corona profile follows a r^{-1} power law, the conformation of a grafted chain is identical to that of a chain in a reference melt, implying a high mutual penetration of the coronas from different particles. The brush crowding leads to topological confinement of the chain dynamics: (i) At local scales, the segmental dynamics is unchanged compared to the reference melt, while (ii) at the scale of the chain, the dynamics appears to be slowed down; (iii) by performing a mode analysis in terms of end-fixed Rouse chains, the slower dynamics is tracked to topological confinement within the cone spanned by the adjacent grafts; (iv) by adding 50% matrix chains, the topological confinement sensed by the grafted chain is lifted partially and the apparent chain motion is accelerated. We observe a crossover from pure Rouse motion at short times to topological confined motion beyond the time when the segmental mean squared displacement has reached the distance to the next graft.
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Affiliation(s)
- C Mark
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - O Holderer
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenberstraße 1, 85747 Garching, Germany
| | - J Allgaier
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - E Hübner
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - W Pyckhout-Hintzen
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - M Zamponi
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenberstraße 1, 85747 Garching, Germany
| | - A Radulescu
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenberstraße 1, 85747 Garching, Germany
| | - A Feoktystov
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenberstraße 1, 85747 Garching, Germany
| | - M Monkenbusch
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - N Jalarvo
- Forschungszentrum Jülich GmbH, JCNS at SNS-Oak Ridge National Laboratory (ORNL), 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, USA
| | - D Richter
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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33
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Zhang M, Askar S, Torkelson JM, Brinson LC. Stiffness Gradients in Glassy Polymer Model Nanocomposites: Comparisons of Quantitative Characterization by Fluorescence Spectroscopy and Atomic Force Microscopy. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00917] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Min Zhang
- Department
of Materials Science and Engineering, ‡Department of Chemical and Biological
Engineering, and §Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Shadid Askar
- Department
of Materials Science and Engineering, ‡Department of Chemical and Biological
Engineering, and §Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - John M. Torkelson
- Department
of Materials Science and Engineering, ‡Department of Chemical and Biological
Engineering, and §Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - L. Catherine Brinson
- Department
of Materials Science and Engineering, ‡Department of Chemical and Biological
Engineering, and §Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, United States
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34
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Cheng S, Carroll B, Bocharova V, Carrillo JM, Sumpter BG, Sokolov AP. Focus: Structure and dynamics of the interfacial layer in polymer nanocomposites with attractive interactions. J Chem Phys 2017; 146:203201. [DOI: 10.1063/1.4978504] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Shiwang Cheng
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Bobby Carroll
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Vera Bocharova
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Jan-Michael Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Bobby G. Sumpter
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Alexei P. Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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35
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Mirigian S, Schweizer KS. Influence of chemistry, interfacial width, and non-isothermal conditions on spatially heterogeneous activated relaxation and elasticity in glass-forming free standing films. J Chem Phys 2017; 146:203301. [PMID: 28571330 DOI: 10.1063/1.4974766] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Stephen Mirigian
- Departments of Materials Science and Chemistry, University of Illinois, 1304 West Green Street, Urbana, Illinois 61801, USA
| | - Kenneth S. Schweizer
- Departments of Materials Science and Chemistry, University of Illinois, 1304 West Green Street, Urbana, Illinois 61801, USA
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36
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Cheng S, Carroll B, Lu W, Fan F, Carrillo JMY, Martin H, Holt AP, Kang NG, Bocharova V, Mays JW, Sumpter BG, Dadmun M, Sokolov AP. Interfacial Properties of Polymer Nanocomposites: Role of Chain Rigidity and Dynamic Heterogeneity Length Scale. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02816] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Shiwang Cheng
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Bobby Carroll
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Wei Lu
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Fei Fan
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Jan-Michael Y. Carrillo
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Halie Martin
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Adam P. Holt
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Nam-Goo Kang
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Vera Bocharova
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Jimmy W. Mays
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Bobby G. Sumpter
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Mark Dadmun
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Alexei P. Sokolov
- Chemical
Sciences Division, ‡Center for Nanophase Materials Sciences, and §Computational
Science and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics
and Astronomy and ⊥Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
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37
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Cheng S, Xie SJ, Carrillo JMY, Carroll B, Martin H, Cao PF, Dadmun MD, Sumpter BG, Novikov VN, Schweizer KS, Sokolov AP. Big Effect of Small Nanoparticles: A Shift in Paradigm for Polymer Nanocomposites. ACS NANO 2017; 11:752-759. [PMID: 28051845 DOI: 10.1021/acsnano.6b07172] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Polymer nanocomposites (PNCs) are important materials that are widely used in many current technologies and potentially have broader applications in the future due to their excellent property tunability, light weight, and low cost. However, expanding the limits in property enhancement remains a fundamental scientific challenge. Here, we demonstrate that well-dispersed, small (diameter ∼1.8 nm) nanoparticles with attractive interactions lead to unexpectedly large and qualitatively different changes in PNC structural dynamics in comparison to conventional nanocomposites based on particles of diameters ∼10-50 nm. At the same time, the zero-shear viscosity at high temperatures remains comparable to that of the neat polymer, thereby retaining good processability and resolving a major challenge in PNC applications. Our results suggest that the nanoparticle mobility and relatively short lifetimes of nanoparticle-polymer associations open qualitatively different horizons in the tunability of macroscopic properties in nanocomposites with a high potential for the development of advanced functional materials.
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Affiliation(s)
| | - Shi-Jie Xie
- Departments of Materials Science and Chemistry, Frederick Seitz Materials Research Laboratory, University of Illinois , Urbana, Illinois 61801, United States
| | | | | | | | | | | | | | | | - Kenneth S Schweizer
- Departments of Materials Science and Chemistry, Frederick Seitz Materials Research Laboratory, University of Illinois , Urbana, Illinois 61801, United States
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Klonos P, Kulyk K, Borysenko MV, Gun’ko VM, Kyritsis A, Pissis P. Effects of Molecular Weight below the Entanglement Threshold on Interfacial Nanoparticles/Polymer Dynamics. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01931] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Panagiotis Klonos
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
| | - Kostiantyn Kulyk
- Department of Physics, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Mykola V. Borysenko
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Street, Kiev 03164, Ukraine
| | - Vladimir M. Gun’ko
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Street, Kiev 03164, Ukraine
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
| | - Polycarpos Pissis
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
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39
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Griffin PJ, Bocharova V, Middleton LR, Composto RJ, Clarke N, Schweizer KS, Winey KI. Influence of the Bound Polymer Layer on Nanoparticle Diffusion in Polymer Melts. ACS Macro Lett 2016; 5:1141-1145. [PMID: 35658173 DOI: 10.1021/acsmacrolett.6b00649] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We measure the center-of-mass diffusion of silica nanoparticles (NPs) in entangled poly(2-vinylpyridine) (P2VP) melts using Rutherford backscattering spectrometry. While these NPs are well within the size regime where enhanced, nonhydrodynamic NP transport is theoretically predicted and has been observed experimentally (2RNP/dtube ≈ 3, where 2RNP is the NP diameter and dtube is the tube diameter), we find that the diffusion of these NPs in P2VP is in fact well-described by the hydrodynamic Stokes-Einstein relation. The effective NP diameter 2Reff is significantly larger than 2RNP and strongly dependent on P2VP molecular weight, consistent with the presence of a bound polymer layer on the NP surface with thickness heff ≈ 1.1Rg. Our results show that the bound polymer layer significantly augments the NP hydrodynamic size in polymer melts with attractive polymer-NP interactions and effectively transitions the mechanism of NP diffusion from the nonhydrodynamic to hydrodynamic regime, particularly at high molecular weights where NP transport is expected to be notably enhanced. Furthermore, these results provide the first experimental demonstration that hydrodynamic NP transport in polymer melts requires particles of size ≳5dtube, consistent with recent theoretical predictions.
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Affiliation(s)
- Philip J. Griffin
- Department
of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Vera Bocharova
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - L. Robert Middleton
- Department
of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Russell J. Composto
- Department
of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Nigel Clarke
- Department
of Physics, University of Sheffield, Sheffield, S3 7RH, United Kingdom
| | - Kenneth S. Schweizer
- Department
of Materials Science and Engineering, University of Illinois, Urbana, Illinois 61801, United States
| | - Karen I. Winey
- Department
of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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40
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Holt AP, Bocharova V, Cheng S, Kisliuk AM, White BT, Saito T, Uhrig D, Mahalik JP, Kumar R, Imel AE, Etampawala T, Martin H, Sikes N, Sumpter BG, Dadmun MD, Sokolov AP. Controlling Interfacial Dynamics: Covalent Bonding versus Physical Adsorption in Polymer Nanocomposites. ACS NANO 2016; 10:6843-52. [PMID: 27337392 DOI: 10.1021/acsnano.6b02501] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
It is generally believed that the strength of the polymer-nanoparticle interaction controls the modification of near-interface segmental mobility in polymer nanocomposites (PNCs). However, little is known about the effect of covalent bonding on the segmental dynamics and glass transition of matrix-free polymer-grafted nanoparticles (PGNs), especially when compared to PNCs. In this article, we directly compare the static and dynamic properties of poly(2-vinylpyridine)/silica-based nanocomposites with polymer chains either physically adsorbed (PNCs) or covalently bonded (PGNs) to identical silica nanoparticles (RNP = 12.5 nm) for three different molecular weight (MW) systems. Interestingly, when the MW of the matrix is as low as 6 kg/mol (RNP/Rg = 5.4) or as high as 140 kg/mol (RNP/Rg= 1.13), both small-angle X-ray scattering and broadband dielectric spectroscopy show similar static and dynamic properties for PNCs and PGNs. However, for the intermediate MW of 18 kg/mol (RNP/Rg = 3.16), the difference between physical adsorption and covalent bonding can be clearly identified in the static and dynamic properties of the interfacial layer. We ascribe the differences in the interfacial properties of PNCs and PGNs to changes in chain stretching, as quantified by self-consistent field theory calculations. These results demonstrate that the dynamic suppression at the interface is affected by the chain stretching; that is, it depends on the anisotropy of the segmental conformations, more so than the strength of the interaction, which suggests that the interfacial dynamics can be effectively tuned by the degree of stretching-a parameter accessible from the MW or grafting density.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Nicole Sikes
- Department of Chemistry, Columbus State University , Columbus, Georgia 33232, United States
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Affiliation(s)
- R. Casalini
- Chemistry Division, Naval Research Laboratory, Washington, D.C. 20375-5342, United States
| | - C. M. Roland
- Chemistry Division, Naval Research Laboratory, Washington, D.C. 20375-5342, United States
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Cheng S, Holt AP, Wang H, Fan F, Bocharova V, Martin H, Etampawala T, White BT, Saito T, Kang NG, Dadmun MD, Mays JW, Sokolov AP. Unexpected Molecular Weight Effect in Polymer Nanocomposites. PHYSICAL REVIEW LETTERS 2016; 116:038302. [PMID: 26849618 DOI: 10.1103/physrevlett.116.038302] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Indexed: 05/26/2023]
Abstract
The properties of the interfacial layer between the polymer matrix and nanoparticles largely determine the macroscopic properties of polymer nanocomposites (PNCs). Although the static thickness of the interfacial layer was found to increase with the molecular weight (MW), the influence of MW on segmental relaxation and the glass transition in this layer remains to be explored. In this Letter, we show an unexpected MW dependence of the interfacial properties in PNC with attractive polymer-nanoparticle interactions: the thickness of the interfacial layer with hindered segmental relaxation decreases as MW increases, in sharp contrast to theoretical predictions. Further analyses reveal a reduction in mass density of the interfacial layer with increasing MW, which can elucidate these unexpected dynamic effects. Our observations call for a significant revision of the current understandings of PNCs and suggest interesting ways to tailor their properties.
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Affiliation(s)
- Shiwang Cheng
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Adam P Holt
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Huiqun Wang
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Fei Fan
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Vera Bocharova
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Halie Martin
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Thusitha Etampawala
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - B Tyler White
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Tomonori Saito
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Nam-Goo Kang
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Mark D Dadmun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Jimmy W Mays
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Alexei P Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
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