1
|
Mei B, Schweizer KS. Penetrant shape effects on activated dynamics and selectivity in polymer melts and networks based on self-consistent cooperative hopping theory. SOFT MATTER 2023; 19:8744-8763. [PMID: 37937332 DOI: 10.1039/d3sm01139a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
We generalize and apply the microscopic self-consistent cooperative hopping theory for activated penetrant dynamics in polymer melts and crosslinked networks to address the role of highly variable non-spherical molecular shape. The focus is on vastly different shaped penetrants that have identical space filling volume in order to isolate how non-spherical shape explicitly modifies dynamics over a wide range of temperature down to the kinetic glass transition temperature. The theory relates intramolecular and intermolecular structure and kinetic constraints, and reveals how different solvation packing of polymer monomers around variable shaped penetrants impact penetrant hopping. A highly shape-dependent penetrant activated relaxation, including alpha time decoupling and trajectory level cooperativity of the hopping process, is predicted in the deeply supercooled regime for relatively larger penetrants which is sensitive to whether the polymer matrix is a melt or heavily crosslinked network. In contrast, for smaller size penetrants or at high/medium temperatures the effect of isochoric penetrant shape is relatively weak. We propose an aspect ratio variable that organizes how penetrant shape influences the activated relaxation times, leading to a (near) collapse or master curve. The relative absolute values of the penetrant relaxation time (inverse hopping rate) in polymer melts versus in crosslinked networks are found to be opposite when compared at a common absolute temperature versus when they are compared at a fixed value of distance from the glass transition based on the variable Tg/T with Tg the glass transition temperature. Quantitative comparison with recent diffusion experiments on chemically complex molecular penetrants of variable shape but fixed volume in crosslinked networks reveals good agreement, and testable new predictions are made. Extension of the theoretical approach to more complex systems of high experimental interest are discussed, including applications to realize selective transport in membrane separation applications.
Collapse
Affiliation(s)
- Baicheng Mei
- Department of Materials Science, University of Illinois, Urbana, IL 61801, USA.
- Materials Research Laboratory, University of Illinois, Urbana, IL 61801, USA
| | - Kenneth S Schweizer
- Department of Materials Science, University of Illinois, Urbana, IL 61801, USA.
- Department of Chemistry, University of Illinois, Urbana, IL 61801, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA
- Materials Research Laboratory, University of Illinois, Urbana, IL 61801, USA
| |
Collapse
|
2
|
Swain A, Adarsh S, Biswas A, Bose S, Benicewicz BC, Kumar SK, Basu JK. Enhanced efficiency of water desalination in nanostructured thin-film membranes with polymer grafted nanoparticles. NANOSCALE 2023. [PMID: 37366152 DOI: 10.1039/d3nr00777d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Polyamide composite (PA-TFC) membranes are the state-of-the-art ubiquitous platforms to desalinate water at scale. We have developed a novel, transformative platform where the performance of such membranes is significantly and controllably improved by depositing thin films of polymethylacrylate [PMA] grafted silica nanoparticles (PGNPs) through the venerable Langmuir-Blodgett method. Our key practically important finding is that these constructs can have unprecedented selectivity values (i.e., ∼250-3000 bar-1, >99.0% salt rejection) at reduced feed water pressure (i.e., reduced cost) while maintaining acceptable water permeance A (= 2-5 L m-2 h-1 Bar-1) with as little as 5-7 PGNP layers. We also observe that the transport of solvent and solute are governed by different mechanisms, unlike gas transport, leading to independent control of A and selectivity. Since these membranes can be formulated using simple and low cost self-assembly methods, our work opens a new direction towards development of affordable, scalable water desalination methods.
Collapse
Affiliation(s)
- Aparna Swain
- Department of Physics, Indian Institute of Science Bangalore, 560012, India.
| | - S Adarsh
- Department of Physics, Indian Institute of Science Bangalore, 560012, India.
| | - Ashish Biswas
- Department of Physics, Indian Institute of Science Bangalore, 560012, India.
| | - Suryasarathi Bose
- Department of Materials Engineering, Indian Institute of Science Bangalore, 560012, Karnataka, India
| | - Brian C Benicewicz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, 29208, South Carolina, USA
| | - Sanat K Kumar
- Department of Chemical Engineering, Columbia University, New York, 10027, New York, USA
| | - J K Basu
- Department of Physics, Indian Institute of Science Bangalore, 560012, India.
| |
Collapse
|
3
|
Mei B, Lin TW, Sheridan GS, Evans CM, Sing CE, Schweizer KS. How Segmental Dynamics and Mesh Confinement Determine the Selective Diffusivity of Molecules in Cross-Linked Dense Polymer Networks. ACS CENTRAL SCIENCE 2023; 9:508-518. [PMID: 36968535 PMCID: PMC10037493 DOI: 10.1021/acscentsci.2c01373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Indexed: 06/18/2023]
Abstract
The diffusion of molecules ("penetrants") of variable size, shape, and chemistry through dense cross-linked polymer networks is a fundamental scientific problem broadly relevant in materials, polymer, physical, and biological chemistry. Relevant applications include separation membranes, barrier materials, drug delivery, and nanofiltration. A major open question is the relationship between transport, thermodynamic state, and penetrant and polymer chemical structure. Here we combine experiment, simulation, and theory to unravel these competing effects on penetrant transport in rubbery and supercooled polymer permanent networks over a wide range of cross-link densities, size ratios, and temperatures. The crucial importance of the coupling of local penetrant hopping to polymer structural relaxation and the secondary importance of mesh confinement effects are established. Network cross-links strongly slow down nm-scale polymer relaxation, which greatly retards the activated penetrant diffusion. The demonstrated good agreement between experiment, simulation, and theory provides strong support for the size ratio (penetrant diameter to the polymer Kuhn length) as a key variable and the usefulness of coarse-grained simulation and theoretical models that average over Angstrom scale structure. The developed theory provides an understanding of the physical processes underlying the behaviors observed in experiment and simulation and suggests new strategies for enhancing selective polymer membrane design.
Collapse
Affiliation(s)
- Baicheng Mei
- Department
of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Materials
Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Tsai-Wei Lin
- Department
of Chemical & Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
- Materials
Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Grant S. Sheridan
- Department
of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Materials
Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Christopher M. Evans
- Department
of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Department
of Chemical & Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
- Materials
Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Charles E. Sing
- Department
of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Department
of Chemical & Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
- Materials
Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| | - Kenneth S. Schweizer
- Department
of Materials Science, University of Illinois, Urbana, Illinois 61801, United States
- Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
- Department
of Chemical & Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, United States
- Materials
Research Laboratory, University of Illinois, Urbana, Illinois 61801, United States
| |
Collapse
|
4
|
Revelas CJ, Sgouros AP, Lakkas AT, Theodorou DN. Addressing Nanocomposite Systems via 3D-SCFT: Assessment of Smearing Approximation and Irregular Grafting Distributions. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- Constantinos J. Revelas
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece
| | - Aristotelis P. Sgouros
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece
| | - Apostolos T. Lakkas
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece
| | - Doros N. Theodorou
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece
| |
Collapse
|
5
|
Wu W, Singh M, Zhai Y, Masud A, Tonny W, Yuan C, Yin R, Al-Enizi AM, Bockstaller MR, Matyjaszewski K, Douglas JF, Karim A. Facile Entropy-Driven Segregation of Imprinted Polymer-Grafted Nanoparticle Brush Blends by Solvent Vapor Annealing Soft Lithography. ACS APPLIED MATERIALS & INTERFACES 2022; 14:45765-45774. [PMID: 36174114 DOI: 10.1021/acsami.2c11134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Polymer-grafted nanoparticles (PGNPs) have attracted extensive research interest due to their potential for enhancing mechanical and electrical properties of both bulk polymer composite materials, as well as thin polymer films incorporating these nanoparticles (NPs). In previous studies, we have shown that an entropic driving force serves to organize low-molecular-mass PGNPs in imprinted blend films of PGNPs with low-molecular-mass homopolymers. In this work, we developed a novel solvent vapor annealing soft lithography (SVA-SL) method to overcome the technical difficulties in processing the high-molecular-mass PGNP blends due to the intrinsically sluggish melt annealing kinetics found in the phase separation of these blend PGNP materials. In particular, we utilized SVA-SL to create nanopatterns in blends of PGNPs having relatively high-molecular-mass-grafted layers but with cores of NPs having greatly different sizes. The minimization of the entropic free energy in the present system corresponded to larger PGNPs partitioning almost exclusively into the "mesa" regions of the imprinted PGNP blend films, as quantified by the estimation of the partition coefficient, Kp. The use of the SVA-SL processing method is important because it allows facile imprint patterning of PGNP materials and large-scale organization of the PGNPs even when the grafted chain lengths are long enough for the chains to be highly entangled, allowing enhanced thermo-mechanical property enhancements of the resulting films and a corresponding extended range of potential nanotech applications.
Collapse
Affiliation(s)
- Wenjie Wu
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Maninderjeet Singh
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Yue Zhai
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Ali Masud
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Wafa Tonny
- Department of Materials Science and Engineering, University of Houston, Houston, Texas77204, United States
| | - Chuqing Yuan
- Department of Materials Science and Engineering, University of Houston, Houston, Texas77204, United States
| | - Rongguan Yin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Abdullah M Al-Enizi
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh11451, Saudi Arabia
| | - Michael R Bockstaller
- Department of Materials Science and Engineering, University of Houston, Houston, Texas77204, United States
| | - Krzysztof Matyjaszewski
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Jack F Douglas
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland20899, United States
| | - Alamgir Karim
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| |
Collapse
|
6
|
Elucidation of the physical factors that control activated transport of penetrants in chemically complex glass-forming liquids. Proc Natl Acad Sci U S A 2022; 119:e2210094119. [PMID: 36194629 PMCID: PMC9565165 DOI: 10.1073/pnas.2210094119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Understanding the activated transport of penetrant or tracer atoms and molecules in condensed phases is a challenging problem in chemistry, materials science, physics, and biophysics. Many angstrom- and nanometer-scale features enter due to the highly variable shape, size, interaction, and conformational flexibility of the penetrant and matrix species, leading to a dramatic diversity of penetrant dynamics. Based on a minimalist model of a spherical penetrant in equilibrated dense matrices of hard spheres, a recent microscopic theory that relates hopping transport to local structure has predicted a novel correlation between penetrant diffusivity and the matrix thermodynamic dimensionless compressibility, S0(T) (which also quantifies the amplitude of long wavelength density fluctuations), as a consequence of a fundamental statistical mechanical relationship between structure and thermodynamics. Moreover, the penetrant activation barrier is predicted to have a factorized/multiplicative form, scaling as the product of an inverse power law of S0(T) and a linear/logarithmic function of the penetrant-to-matrix size ratio. This implies an enormous reduction in chemical complexity that is verified based solely on experimental data for diverse classes of chemically complex penetrants dissolved in molecular and polymeric liquids over a wide range of temperatures down to the kinetic glass transition. The predicted corollary that the penetrant diffusion constant decreases exponentially with inverse temperature raised to an exponent determined solely by how S0(T) decreases with cooling is also verified experimentally. Our findings are relevant to fundamental questions in glassy dynamics, self-averaging of angstrom-scale chemical features, and applications such as membrane separations, barrier coatings, drug delivery, and self-healing.
Collapse
|
7
|
Mei B, Schweizer KS. Theory of the Effects of Specific Attractions and Chain Connectivity on the Activated Dynamics and Selective Transport of Penetrants in Polymer Melts. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Baicheng Mei
- Department of Materials Science, University of Illinois, Urbana, Illinois61801, United States
- Materials Research Laboratory, University of Illinois, Urbana, Illinois61801, United States
| | - Kenneth S. Schweizer
- Department of Materials Science, University of Illinois, Urbana, Illinois61801, United States
- Department of Chemistry, University of Illinois, Urbana, Illinois61801, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, Illinois61801, United States
- Materials Research Laboratory, University of Illinois, Urbana, Illinois61801, United States
| |
Collapse
|
8
|
Cappelletti C, Olaechea LM, Ianiro A, Prado-Martínez C, Oveisi E, Weder C, Schrettl S. Metallosupramolecular polymers as precursors for platinum nanocomposites. Polym Chem 2022; 13:1880-1890. [PMID: 35432604 PMCID: PMC8962995 DOI: 10.1039/d2py00071g] [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: 01/17/2022] [Accepted: 03/04/2022] [Indexed: 11/21/2022]
Abstract
Nanocomposites comprised of a polymer matrix and metallic nanoparticles (NPs) can merge the structural features of the matrix material with the functional characteristics of the NPs. While such materials are...
Collapse
Affiliation(s)
- Claudio Cappelletti
- Adolphe Merkle Institute, University of Fribourg Chemin des Verdiers 4 1700 Fribourg Switzerland
| | - Luis M Olaechea
- Adolphe Merkle Institute, University of Fribourg Chemin des Verdiers 4 1700 Fribourg Switzerland
| | - Alessandro Ianiro
- Adolphe Merkle Institute, University of Fribourg Chemin des Verdiers 4 1700 Fribourg Switzerland
| | - Cristina Prado-Martínez
- Adolphe Merkle Institute, University of Fribourg Chemin des Verdiers 4 1700 Fribourg Switzerland
| | - Emad Oveisi
- Interdisciplinary Centre for Electron Microscopy, EPFL 1015 Lausanne Switzerland
| | - Christoph Weder
- Adolphe Merkle Institute, University of Fribourg Chemin des Verdiers 4 1700 Fribourg Switzerland
| | - Stephen Schrettl
- Adolphe Merkle Institute, University of Fribourg Chemin des Verdiers 4 1700 Fribourg Switzerland
| |
Collapse
|
9
|
Izor S, Schantz A, Jawaid A, Grabowski C, Dagher T, Koerner H, Park K, Vaia R. Coexistence and Phase Behavior of Solvent–Polystyrene-Grafted Gold Nanoparticle Systems. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01714] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sarah Izor
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
- UES, Inc., Dayton, Ohio 45432, United States
| | - Allen Schantz
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
| | - Ali Jawaid
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
- UES, Inc., Dayton, Ohio 45432, United States
| | - Chris Grabowski
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
| | - Tony Dagher
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
| | - Hilmar Koerner
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
| | - Kyoungweon Park
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
- UES, Inc., Dayton, Ohio 45432, United States
| | - Richard Vaia
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7702, United States
| |
Collapse
|
10
|
Adhikari S, Nikoubashman A, Leibler L, Rubinstein M, Midya J, Kumar SK. Gas Transport in Interacting Planar Brushes. ACS POLYMERS AU 2021; 1:39-46. [PMID: 35253005 DOI: 10.1021/acspolymersau.1c00006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Recent experiments on melts of spherical nanoparticles (NPs) densely grafted with polymer chains show enhanced gas transport relative to the neat polymer (without NPs). As a means of understanding this unexpected behavior, we consider here the simpler case of two interacting planar brushes, under conditions representing a polymer melt far below its critical point (i.e., where the "free volume" or holes act akin to a poor solvent). Computer simulations illustrate, in agreement with mean-field ideas, that the density profile far away from the walls is flat but with a value that is marginally larger than the corresponding polymer melt under identical state conditions. We find that tracer particles, which represent the gas of interest, segregate preferentially to the grafting surface, with this result being relatively insensitive to the nature of polymer-surface interactions. These brush layers therefore correspond to heterogeneous transport media: the gas molecules near the grafting surface have accelerated dynamics (presumably parallel to the wall) relative to the corresponding polymer melt, but they have slower dynamics in the central region of the brush. We therefore find that gas molecules perform hop-like motions - they spend a significant part of their time in the regions of fast transport, separated by motions where they "hop" from one surface to the other. These phenomena in combination lead to an overall speedup in gas dynamics in these brush layers relative to a polymer melt, in good agreement with the experimental data.
Collapse
Affiliation(s)
- Sabin Adhikari
- Department of Chemical Engineering, Columbia University, New York, NY 10027, USA
| | - Arash Nikoubashman
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Ludwik Leibler
- UMR Gulliver 7083 CNRS, ESPCI Paris, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
| | - Michael Rubinstein
- Department of Mechanical Engineering and Materials Science, Biomedical Engineering, Chemistry, and Physics, Duke University, Durham, NC 27708-0300, USA
| | - Jiarul Midya
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Sanat K Kumar
- Department of Chemical Engineering, Columbia University, New York, NY 10027, USA
| |
Collapse
|
11
|
Wu W, Singh M, Masud A, Wang X, Nallapaneni A, Xiao Z, Zhai Y, Wang Z, Terlier T, Bleuel M, Yuan G, Satija SK, Douglas JF, Matyjaszewski K, Bockstaller MR, Karim A. Control of Phase Morphology of Binary Polymer Grafted Nanoparticle Blend Films via Direct Immersion Annealing. ACS NANO 2021; 15:12042-12056. [PMID: 34255492 DOI: 10.1021/acsnano.1c03357] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
While the phase separation of binary mixtures of chemically different polymer-grafted nanoparticles (PGNPs) is observed to superficially resemble conventional polymer blends, the presence of a "soft" polymer-grafted layer on the inorganic core of these nanoparticles qualitatively alters the phase separation kinetics of these "nanoblends" from the typical pattern of behavior seen in polymer blends and other simple fluids. We investigate this system using a direct immersion annealing method (DIA) that allows for a facile tuning of the PGNPs phase boundary, phase separation kinetics, and the ultimate scale of phase separation after a sufficient "aging" time. In particular, by switching the DIA solvent composition from a selective one (which increases the interaction parameter according to Timmerman's rule) to an overall good solvent for both PGNP components, we can achieve rapid switchability between phase-separated and homogeneous states. Despite a relatively low and non-classical power-law coarsening exponent, the overall phase separation process is completed on a time scale on the order of a few minutes. Moreover, the roughness of the PGNP blend film saturates at a scale that is proportional to the in-plane phase separation pattern scale, as observed in previous blend and block copolymer film studies. The relatively low magnitude of the coarsening exponent n is attributed to a suppression of hydrodynamic interactions between the PGNPs. The DIA method provides a significant opportunity to control the phase separation morphology of PGNP blends by solution processing, and this method is expected to be quite useful in creating advanced materials.
Collapse
Affiliation(s)
- Wenjie Wu
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, United States
| | - Maninderjeet Singh
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, United States
| | - Ali Masud
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, United States
| | - Xiaoteng Wang
- Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Asritha Nallapaneni
- Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Zihan Xiao
- Department of Materials Science and Engineering, University of Houston, Houston, Texas 77204, United States
| | - Yue Zhai
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Zongyu Wang
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Tanguy Terlier
- SIMS Laboratory, Shared Equipment Authority, Rice University, Houston, Texas 77005, United States
| | - Markus Bleuel
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Guangcui Yuan
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Sushil K Satija
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Jack F Douglas
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Krzysztof Matyjaszewski
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Michael R Bockstaller
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Alamgir Karim
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, United States
| |
Collapse
|
12
|
Lakkas AT, Sgouros AP, Revelas CJ, Theodorou DN. Structure and thermodynamics of grafted silica/polystyrene dilute nanocomposites investigated through self-consistent field theory. SOFT MATTER 2021; 17:4077-4097. [PMID: 33729266 DOI: 10.1039/d1sm00078k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Polymer/matrix nanocomposites (PNCs) are materials with exceptional properties. They offer a plethora of promising applications in key industrial sectors. In most cases, it is preferable to disperse the nanoparticles (NPs) homogeneously across the matrix phase. However, under certain conditions NPs might lump together and lead to a composite material with undesirable properties. A common strategy to stabilize the NPs is to graft on their surface polymer chains of the same chemical constitution as the matrix chains. There are several unresolved issues concerning the optimal molar mass and areal density of grafted chains that would ensure best dispersion, given the nanoparticles and the polymer matrix. We propose a model for the prediction of key structural and thermodynamic properties of PNC and apply it to a single spherical silica (SiO2) nanoparticle or planar surface grafted with polystyrene chains embedded at low concentration in a matrix phase of the same chemical constitution. Our model is based on self-consistent field theory, formulated in terms of the Edwards diffusion equation. The properties of the PNC are explored across a broad parameter space, spanning the mushroom regime (low grafting densities, small NPs and chain lengths), the dense brush regime, and the crowding regime (large grafting densities, NP diameters, and chain lengths). We extract several key quantities regarding the distributions and the configurations of the polymer chains, such as the radial density profiles and their decomposition into contributions of adsorbed and free chains, the chains/area profiles, and the tendency of end segments to segregate at the interfaces. Based on our predictions concerning the brush thickness, we revisit the scaling behaviors proposed in the literature and we compare our findings with experiment, relevant simulations, and analytic models, such as Alexander's model for incompressible brushes.
Collapse
Affiliation(s)
- Apostolos T Lakkas
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece.
| | - Aristotelis P Sgouros
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece.
| | - Constantinos J Revelas
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece.
| | - Doros N Theodorou
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece.
| |
Collapse
|
13
|
Sgouros AP, Revelas CJ, Lakkas AT, Theodorou DN. Potential of Mean Force between Bare or Grafted Silica/Polystyrene Surfaces from Self-Consistent Field Theory. Polymers (Basel) 2021; 13:1197. [PMID: 33917245 PMCID: PMC8068000 DOI: 10.3390/polym13081197] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/02/2021] [Accepted: 04/02/2021] [Indexed: 12/20/2022] Open
Abstract
We investigate single and opposing silica plates, either bare of grafted, in contact with vacuum or melt phases, using self-consistent field theory. Solid-polymer and solid-solid nonbonded interactions are described by means of a Hamaker potential, in conjunction with a ramp potential. The cohesive nonbonded interactions are described by the Sanchez-Lacombe or the Helfand free energy densities. We first build our thermodynamic reference by examining single surfaces, either bare or grafted, under various wetting conditions in terms of the corresponding contact angles, the macroscopic wetting functions (i.e., the work of cohesion, adhesion, spreading and immersion), the interfacial free energies and brush thickness. Subsequently, we derive the potential of mean force (PMF) of two approaching bare plates with melt between them, each time varying the wetting conditions. We then determine the PMF between two grafted silica plates separated by a molten polystyrene film. Allowing the grafting density and the molecular weight of grafted chains to vary between the two plates, we test how asymmetries existing in a real system could affect steric stabilization induced by the grafted chains. Additionally, we derive the PMF between two grafted surfaces in vacuum and determine how the equilibrium distance between the two grafted plates is influenced by their grafting density and the molecular weight of grafted chains. Finally, we provide design rules for the steric stabilization of opposing grafted surfaces (or fine nanoparticles) by taking account of the grafting density, the chain length of the grafted and matrix chains, and the asymmetry among the opposing surfaces.
Collapse
Affiliation(s)
- Aristotelis P. Sgouros
- Correspondence: (A.P.S.); (D.N.T.); Tel.: +30-210-772-3216 (A.P.S.); +30-210-772-3157 (D.N.T.)
| | | | | | - Doros N. Theodorou
- School of Chemical Engineering, National Technical University of Athens (NTUA), GR-15780 Athens, Greece; (C.J.R.); (A.T.L.)
| |
Collapse
|
14
|
Midya J, Rubinstein M, Kumar SK, Nikoubashman A. Structure of Polymer-Grafted Nanoparticle Melts. ACS NANO 2020; 14:15505-15516. [PMID: 33084300 PMCID: PMC8056455 DOI: 10.1021/acsnano.0c06134] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The structure of neat melts of polymer-grafted nanoparticles (GNPs) is studied via coarse-grained molecular dynamics simulations. We systematically vary the degree of polymerization and grafting density at fixed nanoparticle (NP) radius and study in detail the shape and size of the GNP coronas. For sufficiently high grafting density, chain sections close to the NP core are extended and form a dry layer. Further away from the NP, there is an interpenetration layer, where the polymer coronas of neighboring GNPs overlap and the chain sections have almost unperturbed conformations. To better understand this partitioning, we develop a two-layer model, representing the grafted polymer around an NP by spherical dry and interpenetration layers. This model quantitatively predicts that the thicknesses of the two layers depend on one universal parameter, x, the degree of overcrowding of grafted chains relative to chains in the melt. Both simulations and theory show that the chain extension free energy is nonmonotonic with increasing chain length at a fixed grafting density, with a well-defined maximum. This maximum is indicative of the crossover from the dry layer-dominated to interpenetration layer-dominated regime, and it could have profound consequences on our understanding of a variety of anomalous transport properties of these GNPs. Our theoretical approach therefore provides a facile means for understanding and designing solvent-free GNP-based materials.
Collapse
Affiliation(s)
- Jiarul Midya
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Michael Rubinstein
- Department of Mechanical Engineering and Materials Science, Biomedical Engineering, Chemistry, and Physics, Duke University, Durham, NC 27708-0300, USA
| | - Sanat K. Kumar
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
| | - Arash Nikoubashman
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
| |
Collapse
|
15
|
Greenfield ML. Representing polymer molecular structure using molecular simulations for the study of liquid sorption and diffusion. Curr Opin Chem Eng 2020. [DOI: 10.1016/j.coche.2020.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
16
|
Yi C, Yang Y, Liu B, He J, Nie Z. Polymer-guided assembly of inorganic nanoparticles. Chem Soc Rev 2019; 49:465-508. [PMID: 31845685 DOI: 10.1039/c9cs00725c] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The self-assembly of inorganic nanoparticles is of great importance in realizing their enormous potentials for broad applications due to the advanced collective properties of nanoparticle ensembles. Various molecular ligands (e.g., small molecules, DNAs, proteins, and polymers) have been used to assist the organization of inorganic nanoparticles into functional structures at different hierarchical levels. Among others, polymers are particularly attractive for use in nanoparticle assembly, because of the complex architectures and rich functionalities of assembled structures enabled by polymers. Polymer-guided assembly of nanoparticles has emerged as a powerful route to fabricate functional materials with desired mechanical, optical, electronic or magnetic properties for a broad range of applications such as sensing, nanomedicine, catalysis, energy storage/conversion, data storage, electronics and photonics. In this review article, we summarize recent advances in the polymer-guided self-assembly of inorganic nanoparticles in both bulk thin films and solution, with an emphasis on the role of polymers in the assembly process and functions of resulting nanostructures. Precise control over the location/arrangement, interparticle interaction, and packing of inorganic nanoparticles at various scales are highlighted.
Collapse
Affiliation(s)
- Chenglin Yi
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, P. R. China.
| | - Yiqun Yang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, P. R. China.
| | - Ben Liu
- Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, Jiangsu 210023, China and Department of Chemistry and Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06268, USA.
| | - Jie He
- Department of Chemistry and Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06268, USA.
| | - Zhihong Nie
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, P. R. China.
| |
Collapse
|