1
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Molecular Dynamic and Dissipative Particle Dynamic Simulation on the Miscibility of NR/CR Blends. Polymers (Basel) 2023; 15:polym15040856. [PMID: 36850139 PMCID: PMC9967134 DOI: 10.3390/polym15040856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/05/2023] [Accepted: 02/07/2023] [Indexed: 02/11/2023] Open
Abstract
Natural rubber (NR) exhibits good elasticity, flexural resistance, wear resistance, and excellent mechanical properties, and it has been widely used in aerospace, transportation, medical, and health fields. For NR, however, the resistance to thermal-oxidation and ozone aging is fairly poor. Although aging properties of NR can be significantly improved with the incorporation of chloroprene rubber (CR) according to some references, the miscibility between NR and CR, the morphologies of the binary blends, and so on are revealed ambiguously. In this work, molecular dynamics simulation (MD) and dissipative particle dynamics (DPD) simulation were carried out to predict the compatibility between natural rubber and chloroprene rubber in view of Flory-Huggins parameters. The morphologies of the blends were obtained with the use of the DPD method. The simulation results were furtherly examined by means of Fourier transform infrared spectroscopy (FT-IR) and dynamic mechanical analysis (DMA). It was found that the miscibility between NR and CR is poor. Nevertheless, the miscibility could be improved when the content of CR is 50% or 90%. In addition, spinodal decomposition with a critical temperature of 390 K would take place according to the phase diagram. Microphase structure such as spherical, lamellar, and bicontinuous phases can be found with different contents of CR in the blends with the results of morphologies analysis.
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2
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Reda H, Chazirakis A, Behbahani AF, Savva N, Harmandaris V. A methodology for determining the local mechanical properties of model atomistic glassy polymeric nanostructured materials. MethodsX 2022; 9:101931. [DOI: 10.1016/j.mex.2022.101931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 11/14/2022] [Indexed: 11/23/2022] Open
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3
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Reda H, Chazirakis A, Power AJ, Harmandaris V. Mechanical Behavior of Polymer Nanocomposites via Atomistic Simulations: Conformational Heterogeneity and the Role of Strain Rate. J Phys Chem B 2022; 126:7429-7444. [DOI: 10.1021/acs.jpcb.2c04597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hilal Reda
- Computation-based Science and Technology Research Center, The Cyprus Institute, Aglantzia, 2121, Nicosia, Cyprus
| | - Anthony Chazirakis
- Institute of Applied and Computational Mathematics, Foundation for Research and Technology - Hellas, Heraklion GR-71110, Greece
| | - Albert J. Power
- 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
| | - 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
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4
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Atomistic-scale analysis of the deformation and failure of polypropylene composites reinforced by functionalized silica nanoparticles. Sci Rep 2021; 11:23108. [PMID: 34845272 PMCID: PMC8630061 DOI: 10.1038/s41598-021-02460-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/12/2021] [Indexed: 12/05/2022] Open
Abstract
Interfacial adhesion between polymer matrix and reinforcing silica nanoparticles plays an important role in strengthening polypropylene (PP) composite. To improve the adhesion strength, the surface of silica nanoparticles can be modified by grafted functional molecules. Using atomistic simulations, we examined the effect of functionalization of silica nanoparticles by hexamethyldisilazane (HMDS) and octyltriethoxysilane (OTES) molecules on the deformation and failure of silica-reinforced PP composite. We found that the ultimate tensile strength (UTS) of PP composite functionalized by OTES (28 MPa) is higher than that of HMDS (25 MPa), which is in turn higher than that passivated only by hydrogen (22 MPa). To understand the underlying mechanistic origin, we calculated the adhesive energy and interfacial strength of the interphase region, and found that both the adhesive energy and interfacial strength are the highest for the silica nanoparticles functionalized by OTES molecules, while both are the lowest by hydrogen. The ultimate failure of the polymer composite is initiated by the cavitation in the interphase region with the lowest mass density, and this cavitation failure mode is common for all the examined PP composites, but the cavitation position is dependent on the tail length of the functional molecules. The present work provides interesting insights into the deformation and cavitation failure mechanisms of the silica-reinforced PP composites, and the findings can be used as useful guidelines in selecting chemical agents for surface treatment of silica nanoparticles.
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5
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Thermoplastic bio-nanocomposites: From measurement of fundamental properties to practical application. Adv Colloid Interface Sci 2021; 292:102419. [PMID: 33934003 DOI: 10.1016/j.cis.2021.102419] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 04/09/2021] [Accepted: 04/10/2021] [Indexed: 11/21/2022]
Abstract
Although the discovery of plastic has revolutionized materials used in many industries and by consumers, their non-biodegradable nature has led to one of the greatest problems of our times: plastic waste in the environment. Bioplastics which are biobased and biodegradable, have been suggested as alternatives for their fossil based counterparts, but their properties often do not meet the requirements that standard plastics would, and are in clear need of improvement. One way to do so is by the addition of nanoparticles which, when homogeneously dispersed, have been reported to result in great improvements. However, in practice, homogenous distribution of nanoparticles is not that trivial due to their tendency to aggregate, also after addition to the polymer matrix. Although theoretical frameworks to prevent this process are available, we feel that the options explored in practice are often rather trial and error in nature. For that reason, we review the theories available, aiming to facilitate the design of the nanocomposites for a sustainable future. We first discuss thermodynamic frameworks which revolve around nanoparticle aggregation. To minimize nanoparticle aggregation, the nanoparticle and polymer can be selected in such a way that they have similar polar and dispersive surface energies. The second part is dedicated to nanocomposite processing, where kinetic effects act on the nanocomposite material therewith influencing its final morphology, although it is good to point out that other factors such as reaggregation also affect the final nanocomposite morphology. The third section is dedicated to how nanoparticles affect the polymer matrix to which they are added. We describe how interactions at an atomic scale, result in the formation of an interphasial region which ultimately leads to changed bulk material properties. From these three sections, we conclude that three parameters are often overlooked when designing nanocomposites, namely the surface energies of the nanoparticles and polymers, the aggregation bond energy or strength, and the interphase region. Therefore, in the fourth section we provide an overview of techniques to identify these three parameters. We finish with a summery and outlook for the design of bio nanocomposites, where we bring all insights from the previous four sections together.
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6
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Mitra A, Trifkovic M, Ponnurangam S. Surface Functionalization-Induced Effects on Nanoparticle Dispersion and Associated Changes in the Thermophysical Properties of Polymer Nanocomposites. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Anindya Mitra
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Milana Trifkovic
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Sathish Ponnurangam
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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7
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Caputo S, Hristov V, Nicola AD, Herbst H, Pizzirusso A, Donati G, Munaò G, Albunia AR, Milano G. Efficient Hybrid Particle-Field Coarse-Grained Model of Polymer Filler Interactions: Multiscale Hierarchical Structure of Carbon Black Particles in Contact with Polyethylene. J Chem Theory Comput 2021; 17:1755-1770. [PMID: 33577311 PMCID: PMC8023654 DOI: 10.1021/acs.jctc.0c01095] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Indexed: 11/28/2022]
Abstract
In the present study, we propose, validate, and give first applications for large-scale systems of coarse-grained models suitable for filler/polymer interfaces based on carbon black (CB) and polyethylene (PE). The computational efficiency of the proposed approach, based on hybrid particle-field models (hPF), allows large-scale simulations of CB primary particles of realistic size (∼20 nm) embedded in PE melts. The molecular detailed models, here introduced, allow a microscopic description of the bound layer, through the analysis of the conformational behavior of PE chains adsorbed on different surface sites of CB primary particles, where the conformational behavior of adsorbed chains is different from models based on flat infinite surfaces. On the basis of the features of the systems, an optimized version of OCCAM code for large-scale (up to more than 8 million of beads) parallel runs is proposed and benchmarked. The computational efficiency of the proposed approach opens the possibility of a computational screening of the bound layer, involving the optimal combination of surface chemistry, size, and shape of CB aggregates and the molecular weight distribution of the polymers achieving an important tool to address the polymer/fillers interface and interphase engineering in the polymer industry.
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Affiliation(s)
- Stefano Caputo
- Dipartimento
di Chimica e Biologia, Università
di Salerno, Via Giovanni Paolo II, 132, I-84084, Fisciano, Salerno, Italy
| | - Velichko Hristov
- Innovation
& Technology, Borealis Polyolefine GmbH, St.-Peter-Straße 25, 4021, Linz, Austria
| | - Antonio De Nicola
- Department
of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata-ken 992-8510, Japan
| | - Harald Herbst
- Innovation
& Technology, Borealis Polyolefine GmbH, St.-Peter-Straße 25, 4021, Linz, Austria
| | - Antonio Pizzirusso
- Dipartimento
di Chimica e Biologia, Università
di Salerno, Via Giovanni Paolo II, 132, I-84084, Fisciano, Salerno, Italy
| | - Greta Donati
- Dipartimento
di Chimica e Biologia, Università
di Salerno, Via Giovanni Paolo II, 132, I-84084, Fisciano, Salerno, Italy
| | - Gianmarco Munaò
- Dipartimento
di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della
Terra, Università degli Studi di
Messina, Viale F. Stagno
d’Alcontres 31, 98166 Messina, Italy
| | | | - Giuseppe Milano
- Dipartimento
di Chimica e Biologia, Università
di Salerno, Via Giovanni Paolo II, 132, I-84084, Fisciano, Salerno, Italy
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8
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Power AJ, Remediakis IN, Harmandaris V. Interface and Interphase in Polymer Nanocomposites with Bare and Core-Shell Gold Nanoparticles. Polymers (Basel) 2021; 13:541. [PMID: 33673125 PMCID: PMC7918087 DOI: 10.3390/polym13040541] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
Metal nanoparticles are used to modify/enhance the properties of a polymer matrix for a broad range of applications in bio-nanotechnology. Here, we study the properties of polymer/gold nanoparticle (NP) nanocomposites through atomistic molecular dynamics, MD, simulations. We probe the structural, conformational and dynamical properties of polymer chains at the vicinity of a gold (Au) NP and a functionalized (core/shell) Au NP, and compare them against the behavior of bulk polyethylene (PE). The bare Au NPs were constructed via a systematic methodology starting from ab-initio calculations and an atomistic Wulff construction algorithm resulting in the crystal shape with the minimum surface energy. For the functionalized NPs the interactions between gold atoms and chemically adsorbed functional groups change their shape. As a model polymer matrix we consider polyethylene of different molecular lengths, from the oligomer to unentangled Rouse like systems. The PE/Au interaction is parametrized via DFT calculations. By computing the different properties the concept of the interface, and the interphase as well, in polymer nanocomposites with metal NPs are critically examined. Results concerning polymer density profiles, bond order parameter, segmental and terminal dynamics show clearly that the size of the interface/interphase, depends on the actual property under study. In addition, the anchored polymeric chains change the behavior/properties, and especially the chain density profile and the dynamics, of the polymer chain at the vicinity of the Au NP.
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Affiliation(s)
- Albert J. Power
- Department of Mathematics and Applied Mathematics, University of Crete, GR-71409 Heraklion, Crete, Greece
- Institute of Applied and Computational Mathematics (IACM), Foundation for Research and Technology Hellas (FORTH), GR-71110 Heraklion, Crete, Greece
| | - Ioannis N. Remediakis
- Department of Materials Science and Technology, University of Crete, GR-71003 Heraklion, Crete, Greece;
- Institute of Electronic Structure and Laser, (IESL), Foundation for Research and Technology Hellas (FORTH), GR-71110 Heraklion, Crete, Greece
| | - Vagelis Harmandaris
- Department of Mathematics and Applied Mathematics, University of Crete, GR-71409 Heraklion, Crete, Greece
- Institute of Applied and Computational Mathematics (IACM), Foundation for Research and Technology Hellas (FORTH), GR-71110 Heraklion, Crete, Greece
- Computation-Based Science and Technology Research Center, The Cyprus Institute, Nicosia 2121, Cyprus
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9
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Jia XM, Qian HJ, Lu ZY. The interfacial structure and dynamics in a polymer nanocomposite containing small attractive nanoparticles: a full atomistic molecular dynamics simulation study. Phys Chem Chem Phys 2020; 22:11400-11408. [PMID: 32374336 DOI: 10.1039/d0cp00799d] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We study the interfacial structure and dynamics of a polymer nanocomposite (PNC) composed of octaaminophenyl polyhedral oligomeric silsesquioxane (OAPS) and poly(2-vinylpyridine) (P2VP) by performing full atomistic molecular dynamics simulations. There are eight aminophenyl groups grafted on the surface of the OAPS particle and the particle has a size comparable to the Kuhn segment of P2VP. These aminophenyl groups can form hydrogen bonds (HBs) with pyridine rings from surrounding P2VP chains. We found that OAPS can form ∼2 HBs on average with surrounding polymer chains. The effect of the HBs is investigated in detail by either switching on or off these HBs in our simulation. By analyzing the interfacial static packing structure and dynamic properties, we demonstrate that the system has an ∼1 nm interface width, similar to the OAPS particle size. We also found that HBs can prevent the further penetration of polymers into the inner zone (grafting layer) of the OAPS, and therefore keep the P2VP chains in the outer layer (>1 nm), remaining bulk-like, which is well consistent with experimental results. In addition, we found that NP diffusion is coupled to the absorbed polymer chains, which also dramatically slows down the diffusion of polymer segments in return. The core-shell model in which the NP and absorbed polymers diffuse as a single object is validated here at the full atomistic level. These results provide atomistic insights into the unique structure and dynamics in the small attractive NP-polymer interfacial region. We hope these results will be helpful for the understanding of peculiar phenomena in attractive polymer nanocomposites containing small NPs.
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Affiliation(s)
- Xiang-Meng Jia
- State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, Jilin University, Changchun 130021, China.
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10
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Malavé V, Killgore JP, Garboczi EJ. Decoupling subsurface inhomogeneities: a 3D finite element approach for contact nanomechanical measurements. NANOTECHNOLOGY 2019; 30:285703. [PMID: 30884477 DOI: 10.1088/1361-6528/ab10b1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Novel material properties can be attained when embedding three-dimensional (3D) nanoparticles (NPs) in a variety of polymeric matrices. These inhomogeneities influence the bulk mechanical response due to the local high modulus mismatch between the particles and the matrix. The degree of the mechanical mismatch that is seen near a composite surface depends on the geometry/shape and spatial location and orientation of the particle with respect to the external contact loading. Isolating each particle's contribution to the surrounding elastic field can be numerically discerned but is experimentally complex, as there are limited direct characterization approaches available at the nanoscale. Atomic force microscopy (AFM) instrumentation is one such method that can quantify subsurface particle stiffness effects on nanocomposites with a resolution of a few nanometers. This work studies the spatial and geometrical effects of subsurface silver NPs on the local composite stiffness of a polystyrene matrix using 3D finite element (FE) models to interpret contact resonance (CR) AFM measurements. The present FE-AFM findings suggest both particle shape and particle orientation have a significant role in the degree of uniformity of the stiffness distribution in the embedding matrix. The applied CR-AFM technique shows that the NP geometry can be clearly distinguished when such inhomogeneities are relatively close, 17 nm, to a free surface whereas material-interface measurements at deeper subsurfaces are obscured by experimental noise. This work demonstrates that (i) numerical solutions can assist in qualitatively elucidating nanoinstrumentation stiffness profiles in terms of particle shape and orientation and (ii) CR-AFM measurements can quantify the influence of particle geometry and orientation on the surface nanomechanics of nanocomposite materials.
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Affiliation(s)
- Veruska Malavé
- Applied Chemicals and Materials Division, National Institute of Standards and Technology. Boulder, CO 80305, United States of America
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11
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Hou R, Smith SJD, Wood CD, Mulder RJ, Lau CH, Wang H, Hill MR. Solvation Effects on the Permeation and Aging Performance of PIM-1-Based MMMs for Gas Separation. ACS APPLIED MATERIALS & INTERFACES 2019; 11:6502-6511. [PMID: 30653301 DOI: 10.1021/acsami.8b19207] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Membranes are particularly attractive for lowering the energy intensity of separations as they eliminate phase changes. While many tantalizing polymers are known, limitations in selectivity and stability slightly preclude further development. Mixed-matrix membranes may address these shortcomings. Key to their realization is the intimate mixing between the polymer and the additive to eliminate nonselective transport, improve selectivity, and resist physical aging. Polymers of intrinsic microporosity (PIMs) have inherently promising gas transport properties. Here, we show that porous additives can improve transport and resist aging in PIM-1. We develop a simple, low-cost, and scalable hyper-cross-linked polymer (poly-dichloroxylene, pDCX), which was hydroxylated to form an intimate mixture with the polar PIM-1. Solvent variation allowed control of physical aging rates and improved selectivity for smaller gases. This detailed study has allowed many interactions within mixed matrix membranes to be directly elucidated and presents a practical means to stabilize porous polymers for separation applications.
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Affiliation(s)
- Rujing Hou
- Department of Chemical Engineering , Monash University , Clayton , Victoria 3169 , Australia
| | | | - Colin D Wood
- CSIRO, Australian Resources Research Centre , Kensington , Washington 6152 , United States
| | - Roger J Mulder
- CSIRO , Bag 10 , Clayton South , Victoria 3169 , Australia
| | - Cher Hon Lau
- School of Engineering , University of Edinburgh , Robert Stevenson Road , Edinburgh EH93FB , U.K
| | - Huanting Wang
- Department of Chemical Engineering , Monash University , Clayton , Victoria 3169 , Australia
| | - Matthew R Hill
- Department of Chemical Engineering , Monash University , Clayton , Victoria 3169 , Australia
- CSIRO , Bag 10 , Clayton South , Victoria 3169 , Australia
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12
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Ghasem Zadeh Khorasani M, Silbernagl D, Platz D, Sturm H. Insights into Nano-Scale Physical and Mechanical Properties of Epoxy/Boehmite Nanocomposite Using Different AFM Modes. Polymers (Basel) 2019; 11:E235. [PMID: 30960219 PMCID: PMC6419076 DOI: 10.3390/polym11020235] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/28/2019] [Accepted: 01/29/2019] [Indexed: 11/16/2022] Open
Abstract
Understanding the interaction between nanoparticles and the matrix and the properties of interphase is crucial to predict the macroscopic properties of a nanocomposite system. Here, we investigate the interaction between boehmite nanoparticles (BNPs) and epoxy using different atomic force microscopy (AFM) approaches. We demonstrate benefits of using multifrequency intermodulation AFM (ImAFM) to obtain information about conservative, dissipative and van der Waals tip-surface forces and probing local properties of nanoparticles, matrix and the interphase. We utilize scanning kelvin probe microscopy (SKPM) to probe surface potential as a tool to visualize material contrast with a physical parameter, which is independent from the mechanics of the surface. Combining the information from ImAFM stiffness and SKPM surface potential results in a precise characterization of interfacial region, demonstrating that the interphase is softer than epoxy and boehmite nanoparticles. Further, we investigated the effect of boehmite nanoparticles on the bulk properties of epoxy matrix. ImAFM stiffness maps revealed the significant stiffening effect of boehmite nanoparticles on anhydride-cured epoxy matrix. The energy dissipation of epoxy matrix locally measured by ImAFM shows a considerable increase compared to that of neat epoxy. These measurements suggest a substantial alteration of epoxy structure induced by the presence of boehmite.
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Affiliation(s)
- Media Ghasem Zadeh Khorasani
- Bundesanstalt für Materialforschung und -prüfung (BAM), Div. 6.6, D-12205 Berlin, Germany.
- Department Polymertechnik/Polymerphysik, Technical University of Berlin, D-10587 Berlin, Germany.
| | - Dorothee Silbernagl
- Bundesanstalt für Materialforschung und -prüfung (BAM), Div. 6.6, D-12205 Berlin, Germany.
| | - Daniel Platz
- TU Wien, Institute of Sensor and Actuator Systems, A-1040 Vienna, Austria.
| | - Heinz Sturm
- Bundesanstalt für Materialforschung und -prüfung (BAM), Div. 6.6, D-12205 Berlin, Germany.
- Department Mechanical Engineering and Transport Systems, Technical University of Berlin, D-10587 Berlin, Germany.
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13
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Trazkovich AJ, Wendt MF, Hall LM. Effect of Copolymer Sequence on Local Viscoelastic Properties near a Nanoparticle. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02136] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Alex J. Trazkovich
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, 140 W 19th Ave., Columbus, Ohio 43210, United States
- Cooper Tire & Rubber Company, 701 Lima Ave., Findlay, Ohio 45840, United States
| | - Mitchell F. Wendt
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, 140 W 19th Ave., Columbus, Ohio 43210, United States
| | - Lisa M. Hall
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, 140 W 19th Ave., Columbus, Ohio 43210, United States
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14
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Trazkovich AJ, Wendt MF, Hall LM. Effect of copolymer sequence on structure and relaxation times near a nanoparticle surface. SOFT MATTER 2018; 14:5913-5921. [PMID: 29972193 DOI: 10.1039/c8sm00976g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We simulate a simple nanocomposite consisting of a single spherical nanoparticle surrounded by coarse-grained polymer chains. The polymers are composed of two different monomer types that differ only in their interaction strengths with the nanoparticle. We examine the effect of adjusting copolymer sequence on the structure as well as the end-to-end vector autocorrelation, bond vector autocorrelation, and self-intermediate scattering function relaxation times as a function of distance from the nanoparticle surface. We show how the range and magnitude of the interphase of slowed dynamics surrounding the nanoparticle depend strongly on sequence blockiness. We find that, depending on block length, blocky copolymers can have faster or slower dynamics than a random copolymer. Certain blocky copolymer sequences lead to relaxation times near the nanoparticle surface that are slower than those of either homopolymer system. Thus, tuning copolymer sequence could allow for significant control over the nanocomposite behavior.
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Affiliation(s)
- Alex J Trazkovich
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, USA.
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15
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Wang H, Hor JL, Zhang Y, Liu T, Lee D, Fakhraai Z. Dramatic Increase in Polymer Glass Transition Temperature under Extreme Nanoconfinement in Weakly Interacting Nanoparticle Films. ACS NANO 2018; 12:5580-5587. [PMID: 29792676 DOI: 10.1021/acsnano.8b01341] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Properties of polymers in polymer nanocomposites and nanopores have been shown to deviate from their respective bulk properties due to physical confinement as well as polymer-particle interfacial interactions. However, separating the confinement effects from the interfacial effects under extreme nanoconfinement is experimentally challenging. Capillary rise infiltration enables polymer infiltration into nanoparticle (NP) packings, thereby confining polymers within extremely small pores and dramatically increasing the interfacial area, providing a good system to systematically distinguish the role of each effect on polymer properties. In this study, we investigate the effect of spatial confinement on the glass transition temperature ( Tg) of polystyrene (PS) infiltrated into SiO2 NP films. The degree of confinement is tuned by varying the molecular weight of polymers, the size of NPs (diameters between 11 and 100 nm, producing 3-30 nm average pore sizes), and the fill-fraction of PS in the NP films. We show that in these dense NP packings the Tg of confined PS, which interacts weakly with SiO2 NPs, significantly increases with decreasing pore size such that for the two molecular weights of PS studied the Tg increases by up to 50 K in 11 nm NP packings, while Tg is close to the bulk Tg in 100 nm NP packings. Interestingly, as the fill-fraction of PS is decreased, resulting in the accumulation of the polymer in the contacts between nanoparticles, hence an increased specific interfacial area, the Tg further increases relative to the fully filled films by another 5-8 K, indicating the strong role of geometrical confinement as opposed to the interfacial effects on the measured Tg values.
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Affiliation(s)
- Haonan Wang
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Jyo Lyn Hor
- Department of Chemical and Biomolecular Engineering , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Yue Zhang
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Tianyi Liu
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Zahra Fakhraai
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
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16
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Rissanou AN, Papananou H, Petrakis VS, Doxastakis M, Andrikopoulos KS, Voyiatzis GA, Chrissopoulou K, Harmandaris V, Anastasiadis SH. Structural and Conformational Properties of Poly(ethylene oxide)/Silica Nanocomposites: Effect of Confinement. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00811] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
| | - Hellen Papananou
- Institute
of Electronic Structure and Laser, Foundation for Research and Technology - Hellas,
P.O. Box 1527, 711 10 Heraklion, Crete, Greece
| | | | - Manolis Doxastakis
- Department
of Chemical Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Konstantinos S. Andrikopoulos
- Institute
of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas,
P.O. Box 1414, 265 04 Patras, Greece
| | - George A. Voyiatzis
- Institute
of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas,
P.O. Box 1414, 265 04 Patras, Greece
| | - Kiriaki Chrissopoulou
- Institute
of Electronic Structure and Laser, Foundation for Research and Technology - Hellas,
P.O. Box 1527, 711 10 Heraklion, Crete, Greece
| | - Vagelis Harmandaris
- Institute
of Applied and Computational Mathematics, Foundation for Research and Technology - Hellas, P.O. Box 1385, 711 10 Heraklion, Crete, Greece
| | - Spiros H. Anastasiadis
- Institute
of Electronic Structure and Laser, Foundation for Research and Technology - Hellas,
P.O. Box 1527, 711 10 Heraklion, Crete, Greece
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17
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Jia XM, Shi R, Jiao GS, Chen T, Qian HJ, Lu ZY. Temperature Effect on Interfacial Structure and Dynamics Properties in Polymer/Single-Chain Nanoparticle Composite. MACROMOL CHEM PHYS 2017. [DOI: 10.1002/macp.201700029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xiang-Meng Jia
- State Key Laboratory of Supramolecular Structure and Materials, and Laboratory of Theoretical and Computational Chemistry; Institute of Theoretical Chemistry; Jilin University; Changchun 130023 China
| | - Rui Shi
- State Key Laboratory of Supramolecular Structure and Materials, and Laboratory of Theoretical and Computational Chemistry; Institute of Theoretical Chemistry; Jilin University; Changchun 130023 China
| | - Gui-Sheng Jiao
- State Key Laboratory of Supramolecular Structure and Materials, and Laboratory of Theoretical and Computational Chemistry; Institute of Theoretical Chemistry; Jilin University; Changchun 130023 China
| | - Tao Chen
- State Key Laboratory of Supramolecular Structure and Materials, and Laboratory of Theoretical and Computational Chemistry; Institute of Theoretical Chemistry; Jilin University; Changchun 130023 China
| | - Hu-Jun Qian
- State Key Laboratory of Supramolecular Structure and Materials, and Laboratory of Theoretical and Computational Chemistry; Institute of Theoretical Chemistry; Jilin University; Changchun 130023 China
| | - Zhong-Yuan Lu
- State Key Laboratory of Supramolecular Structure and Materials, and Laboratory of Theoretical and Computational Chemistry; Institute of Theoretical Chemistry; Jilin University; Changchun 130023 China
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18
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Rahimi M, Ramezani-Dakhel H, Zhang R, Ramirez-Hernandez A, Abbott NL, de Pablo JJ. Segregation of liquid crystal mixtures in topological defects. Nat Commun 2017; 8:15064. [PMID: 28452347 PMCID: PMC5414351 DOI: 10.1038/ncomms15064] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 02/24/2017] [Indexed: 01/29/2023] Open
Abstract
The structure and physical properties of liquid crystal (LC) mixtures are a function of composition, and small changes can have pronounced effects on observables, such as phase-transition temperatures. Traditionally, LC mixtures have been assumed to be compositionally homogenous. The results of chemically detailed simulations presented here show that this is not the case; pronounced deviations of the local order from that observed in the bulk at defects and interfaces lead to significant compositional segregation effects. More specifically, two disclination lines are stabilized in this work by introducing into a nematic liquid crystal mixture a cylindrical body that exhibits perpendicular anchoring. It is found that the local composition deviates considerably from that of the bulk at the interface with the cylinder and in the defects, thereby suggesting new assembly and synthetic strategies that may capitalize on the unusual molecular environment provided by liquid crystal mixtures. Liquid crystal mixtures are used in commercial applications and their composition affects their properties. Here Rahimi et al. use atomistic simulations to show that defects influence the molecular arrangement of the mixture components leading to a deviation of the local order from that of the bulk.
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Affiliation(s)
- Mohammad Rahimi
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Hadi Ramezani-Dakhel
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Rui Zhang
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Abelardo Ramirez-Hernandez
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA.,Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Nicholas L Abbott
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Juan J de Pablo
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA.,Argonne National Laboratory, Argonne, Illinois 60439, USA
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19
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Influence of nanoparticle inclusion on the cavity size distribution and accessible volume in polystyrene – Silica nanocomposites. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.08.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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20
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Pfaller S, Possart G, Steinmann P, Rahimi M, Müller-Plathe F, Böhm MC. Investigation of interphase effects in silica-polystyrene nanocomposites based on a hybrid molecular-dynamics-finite-element simulation framework. Phys Rev E 2016; 93:052505. [PMID: 27300943 DOI: 10.1103/physreve.93.052505] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Indexed: 01/26/2023]
Abstract
A recently developed hybrid method is employed to study the mechanical behavior of silica-polystyrene nanocomposites (NCs) under uniaxial elongation. The hybrid method couples a particle domain to a continuum domain. The region of physical interest, i.e., the interphase around a nanoparticle (NP), is treated at molecular resolution, while the surrounding elastic continuum is handled with a finite-element approach. In the present paper we analyze the polymer behavior in the neighborhood of one or two nanoparticle(s) at molecular resolution. The coarse-grained hybrid method allows us to simulate a large polymer matrix region surrounding the nanoparticles. We consider NCs with dilute concentration of NPs embedded in an atactic polystyrene matrix formed by 300 chains with 200 monomer beads. The overall orientation of polymer segments relative to the deformation direction is determined in the neighborhood of the nanoparticle to investigate the polymer response to this perturbation. Calculations of strainlike quantities give insight into the deformation behavior of a system with two NPs and show that the applied strain and the nanoparticle distance have significant influence on the deformation behavior. Finally, we investigate to what extent a continuum-based description may account for the specific effects occurring in the interphase between the polymer matrix and the NPs.
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Affiliation(s)
- Sebastian Pfaller
- Chair of Applied Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 5, D-91058 Erlangen, Germany
| | - Gunnar Possart
- Chair of Applied Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 5, D-91058 Erlangen, Germany
| | - Paul Steinmann
- Chair of Applied Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 5, D-91058 Erlangen, Germany
| | - Mohammad Rahimi
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Florian Müller-Plathe
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie and Centre of Smart Interfaces, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, D-64287 Darmstadt, Germany
| | - Michael C Böhm
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie and Centre of Smart Interfaces, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, D-64287 Darmstadt, Germany
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21
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Choi J, Shin H, Cho M. A multiscale mechanical model for the effective interphase of SWNT/epoxy nanocomposite. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.02.041] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Wang Z, Lv Q, Chen S, Li C, Sun S, Hu S. Effect of Interfacial Bonding on Interphase Properties in SiO2/Epoxy Nanocomposite: A Molecular Dynamics Simulation Study. ACS APPLIED MATERIALS & INTERFACES 2016; 8:7499-508. [PMID: 26927032 DOI: 10.1021/acsami.5b11810] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Atomistic molecular dynamics simulations have been performed to explore the effect of interfacial bonding on the interphase properties of a nanocomposite system that consists of a silica nanoparticle and the highly cross-linked epoxy matrix. For the structural properties, results show that interfacial covalent bonding can broaden the interphase region by increasing the radial effect range of fluctuated mass density and oriented chains, as well as strengthen the interphase region by improving the thermal stability of interfacial van der Waals excluded volume and reducing the proportion of cis conformers of epoxy segments. The improved thermal stability of the interphase region in the covalently bonded model results in an increase of ∼21 K in the glass transition temperature (Tg) compared to that of the pure epoxy. It is also found that interfacial covalent bonding mainly restricts the volume thermal expansion of the model at temperatures near or larger than Tg. Furthermore, investigations from mean-square displacement and fraction of immobile atoms point out that interfacial covalent and noncovalent bonding induces lower and higher mobility of interphase atoms than that of the pure epoxy, respectively. The obtained critical interfacial bonding ratio when the interphase and matrix atoms have the same mobility is 5.8%. These results demonstrate that the glass transitions of the interphase and matrix will be asynchronous when the interfacial bonding ratio is not 5.8%. Specifically, the interphase region will trigger the glass transition of the matrix when the ratio is larger than 5.8%, whereas it restrains the glass transition of the matrix when the ratio is smaller than 5.8%.
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Affiliation(s)
- Zhikun Wang
- College of Science, China University of Petroleum , Qingdao 266580 Shandong Province, P. R. China
| | - Qiang Lv
- College of Science, China University of Petroleum , Qingdao 266580 Shandong Province, P. R. China
| | - Shenghui Chen
- College of Science, China University of Petroleum , Qingdao 266580 Shandong Province, P. R. China
| | - Chunling Li
- College of Science, China University of Petroleum , Qingdao 266580 Shandong Province, P. R. China
- Key Laboratory of New Energy Physics & Materials Science in Universities of Shandong (China University of Petroleum) , Qingdao 266580 Shandong Province, P. R. China
| | - Shuangqing Sun
- College of Science, China University of Petroleum , Qingdao 266580 Shandong Province, P. R. China
- Key Laboratory of New Energy Physics & Materials Science in Universities of Shandong (China University of Petroleum) , Qingdao 266580 Shandong Province, P. R. China
| | - Songqing Hu
- College of Science, China University of Petroleum , Qingdao 266580 Shandong Province, P. R. China
- Key Laboratory of New Energy Physics & Materials Science in Universities of Shandong (China University of Petroleum) , Qingdao 266580 Shandong Province, P. R. China
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23
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Wu E, Garde S. Understanding n-Octane Behavior near Graphene with Scaled Solvent-Solute Attractions. J Phys Chem B 2016; 120:2033-42. [PMID: 26716462 DOI: 10.1021/acs.jpcb.5b10262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We employ molecular dynamics simulations of n-octane near a layered graphene surface to study the related phenomena of solvation, density fluctuations, wettability, and structure and dynamics of n-octane molecules in the inhomogeneous interfacial environment. That solvation in bulk n-octane displays a lengthscale-dependent crossover similar to that of hydrophobic solvation in water is known. Here we show that, near an extended graphene interface having attractive interactions with n-octane, lengthscale-dependent solvation is similar to that in the bulk and displays a small to large crossover. However, as the n-octane-graphene interactions are reduced to make the surface increasingly solvophobic, the crossover behavior is modulated and essentially absent near the most solvophobic surfaces, similar to that in water near hydrophobic interfaces. We show that the macroscopic measure of wettability, namely, the contact angle, characterizes n-octane-graphene coupling over a limited range of attractions. In contrast, molecular measures such as the free energy of cavity formation or the local compressibility in the interfacial region provide an effective measure of this coupling over a broader range of attractions. Finally, as n-octane-graphene attractions are increased, the n-octane liquid displays a wetting transition and corresponding change from sigmoidal to layered density profile. Analysis of the local structure shows that n-octane molecules prefer approximately linear conformations and surface-parallel orientations near the graphene surface, and their translational dynamics slow down with increasing n-octane-graphene attractions. Our study highlights molecular scale behavior of n-octane molecules that is relevant to understanding nanoparticle-solvent coupling in composite materials with enhanced mechanical or thermal properties.
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Affiliation(s)
- Eugene Wu
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, and Center for Materials, Devices, and Integrated Systems, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Shekhar Garde
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, and Center for Materials, Devices, and Integrated Systems, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
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24
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Sethuraman V, Pryamitsyn V, Ganesan V. Influence of molecular weight and degree of segregation on local segmental dynamics of ordered block copolymers. ACTA ACUST UNITED AC 2016. [DOI: 10.1002/polb.23985] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
| | - Victor Pryamitsyn
- Department of Chemical Engineering; University of Texas at Austin; Austin Texas 78712
| | - Venkat Ganesan
- Department of Chemical Engineering; University of Texas at Austin; Austin Texas 78712
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25
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Karatrantos A, Clarke N, Kröger M. Modeling of Polymer Structure and Conformations in Polymer Nanocomposites from Atomistic to Mesoscale: A Review. POLYM REV 2016. [DOI: 10.1080/15583724.2015.1090450] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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26
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Langeloth M, Sugii T, Böhm MC, Müller-Plathe F. The glass transition in cured epoxy thermosets: A comparative molecular dynamics study in coarse-grained and atomistic resolution. J Chem Phys 2015; 143:243158. [DOI: 10.1063/1.4937627] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Michael Langeloth
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie and Center of Smart Interfaces, Technische Universität Darmstadt, Alarich Weiss Straße 4, D-64287 Darmstadt, Germany
| | - Taisuke Sugii
- Center for Technology Innovation – Mechanical Engineering, Research & Development Group, Hitachi, Ltd., 832-2, Horiguchi, Hitachinaka, Ibaraki 312-0034, Japan
| | - Michael C. Böhm
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie and Center of Smart Interfaces, Technische Universität Darmstadt, Alarich Weiss Straße 4, D-64287 Darmstadt, Germany
| | - Florian Müller-Plathe
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie and Center of Smart Interfaces, Technische Universität Darmstadt, Alarich Weiss Straße 4, D-64287 Darmstadt, Germany
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27
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Gharib-Zahedi MR, Tafazzoli M, Böhm MC, Alaghemandi M. Interfacial thermal transport and structural preferences in carbon nanotube–polyamide-6,6 nanocomposites: how important are chemical functionalization effects? Phys Chem Chem Phys 2015; 17:14502-12. [DOI: 10.1039/c5cp00752f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We investigate the influence of chemically functionalized CNTs on the structural properties of the surrounding polyamide-6,6 matrix as well as the interfacial thermal conductivity of polymer–CNT nanocomposites.
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Affiliation(s)
| | - Mohsen Tafazzoli
- Department of Chemistry
- Sharif University of Technology
- 11365-9516 Tehran
- Iran
| | - Michael C. Böhm
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- D-64287 Darmstadt
- Germany
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