1
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Kemppainen J, Gissinger JR, Gowtham S, Odegard GM. LUNAR: Automated Input Generation and Analysis for Reactive LAMMPS Simulations. J Chem Inf Model 2024. [PMID: 38926930 DOI: 10.1021/acs.jcim.4c00730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
Generating simulation-ready molecular models for the LAMMPS molecular dynamics (MD) simulation software package is a difficult task and impedes the more widespread and efficient use of MD in materials design and development. Fixed-bond force fields generally require manual assignment of atom types, bonded interactions, charges, and simulation domain sizes. A new LAMMPS pre- and postprocessing toolkit (LUNAR) is presented that efficiently builds molecular systems for LAMMPS. LUNAR automatically assigns atom types, generates bonded interactions, assigns charges, and provides initial configuration methods to generate large molecular systems. LUNAR can also incorporate chemical reactivity into simulations by facilitating the use of the REACTER protocol. Additionally, LUNAR provides postprocessing for free volume calculations, cure characterization calculations, and property predictions from LAMMPS thermodynamic outputs. LUNAR has been validated via building and simulation of pure epoxy and cyanate ester polymer systems with a comparison of the corresponding predicted structures and properties to benchmark values, including experimental results from the literature. LUNAR provides the tools for the computationally driven development of next-generation composite materials in the Integrated Computational Materials Engineering (ICME) and Materials Genome Initiative (MGI) frameworks. LUNAR is written in Python with the usage of NumPy and can be used via a graphical user interface, a command line interface, or an integrated design environment. LUNAR is freely available via GitHub.
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Affiliation(s)
- Josh Kemppainen
- Michigan Technological University, Houghton, Michigan 49931, United States
| | - Jacob R Gissinger
- Stevens Institute of Technology, Hoboken, New Jersey 07030, United States
| | - S Gowtham
- Michigan Technological University, Houghton, Michigan 49931, United States
| | - Gregory M Odegard
- Michigan Technological University, Houghton, Michigan 49931, United States
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2
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Choi SH, Kim JH, Ahn J, Kim T, Jung Y, Won D, Bang J, Pyun KR, Jeong S, Kim H, Kim YG, Ko SH. Phase patterning of liquid crystal elastomers by laser-induced dynamic crosslinking. NATURE MATERIALS 2024; 23:834-843. [PMID: 38532072 DOI: 10.1038/s41563-024-01845-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 02/21/2024] [Indexed: 03/28/2024]
Abstract
Liquid crystal elastomers hold promise in various fields due to their reversible transition of mechanical and optical properties across distinct phases. However, the lack of local phase patterning techniques and irreversible phase programming has hindered their broad implementation. Here we introduce laser-induced dynamic crosslinking, which leverages the precision and control offered by laser technology to achieve high-resolution multilevel patterning and transmittance modulation. Incorporation of allyl sulfide groups enables adaptive liquid crystal elastomers that can be reconfigured into desired phases or complex patterns. Laser-induced dynamic crosslinking is compatible with existing processing methods and allows the generation of thermo- and strain-responsive patterns that include isotropic, polydomain and monodomain phases within a single liquid crystal elastomer film. We show temporary information encryption at body temperature, expanding the functionality of liquid crystal elastomer devices in wearable applications.
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Affiliation(s)
- Seok Hwan Choi
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Ju Hee Kim
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Jiyong Ahn
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Taegyeom Kim
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Yeongju Jung
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Daeyeon Won
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Junhyuk Bang
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Kyung Rok Pyun
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Seongmin Jeong
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Hyunsu Kim
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Young Gyu Kim
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea.
- Institute of Engineering Research / Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Seoul, Republic of Korea.
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, Korea.
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3
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Kashmari K, Patil SU, Kemppainen J, Shankara G, Odegard GM. Optimal Molecular Dynamics System Size for Increased Precision and Efficiency for Epoxy Materials. J Phys Chem B 2024; 128:4255-4265. [PMID: 38648370 DOI: 10.1021/acs.jpcb.4c00845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Molecular dynamics (MD) simulation is an important tool for predicting thermo-mechanical properties of polymer resins at the nanometer length scale, which is particularly important for efficient computationally driven design of advanced composite materials and structures. Because of the statistical nature of modeling amorphous materials on the nanometer length scale, multiple MD models (replicates) are typically built and simulated for statistical sampling of predicted properties. Larger replicates generally provide higher precision in the predictions but result in higher simulation times. Unfortunately, there is insufficient information in the literature to establish guidelines between MD model size and the resulting precision in predicted thermo-mechanical properties. The objective of this study was to determine the optimal MD model size of epoxy resin to balance efficiency and precision. The results show that an MD model size of 15,000 atoms provides for the fastest simulations without sacrificing precision in the prediction of mass density, elastic properties, strength, and thermal properties of epoxy. The results of this study are important for efficient computational process modeling and integrated computational materials engineering (ICME) for the design of next-generation composite materials for demanding applications.
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Affiliation(s)
- Khatereh Kashmari
- Michigan Technological University, Houghton, Michigan 49931, United States
| | - Sagar U Patil
- Michigan Technological University, Houghton, Michigan 49931, United States
| | - Josh Kemppainen
- Michigan Technological University, Houghton, Michigan 49931, United States
| | - Gowtham Shankara
- Michigan Technological University, Houghton, Michigan 49931, United States
| | - Gregory M Odegard
- Michigan Technological University, Houghton, Michigan 49931, United States
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4
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Hao W, Sui C, Cheng G, Li J, Miao L, Zhao G, Sang Y, Li J, Zhao C, Zhou Y, Zang Z, Zhao Y, He X, Wang C. Dynamic Insights into the Growth Mechanisms of 2D Covalent Organic Frameworks on Graphene Surfaces. ACS NANO 2024; 18:10485-10494. [PMID: 38564695 DOI: 10.1021/acsnano.3c11787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Producing high-quality two-dimensional (2D) covalent organic frameworks (COFs) is crucial for industrial applications. However, this remains significantly challenging with current synthetic techniques. A deep understanding of the intermolecular interactions, reaction temperature, and oligomers is essential to facilitate the growth of highly crystalline COF films. Herein, molecular dynamics simulations were employed to explore the growth of 2D COFs from monomer assemblies on graphene. Our results showed that chain growth reactions dominated the COF surface growth and that van der Waals (vdW) interactions were important in enhancing the crystallinity through monomer preorganization. Moreover, appropriately tuning the reaction temperature improved the COF crystallinity and minimized the effects of amorphous oligomers. Additionally, the strength of the interface between the COF and the graphene substrate indicated that the adhesion force was proportional to the crystallinity of the COF. This work reveals the mechanisms for nucleation and growth of COFs on surfaces and provides theoretical guidance for fabricating high-quality 2D polymer-based crystalline nanomaterials.
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Affiliation(s)
- Weizhe Hao
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
| | - Chao Sui
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Gong Cheng
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Junjiao Li
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
| | - Linlin Miao
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Guoxin Zhao
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Yuna Sang
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
| | - Jiaxuan Li
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Chenxi Zhao
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Yichen Zhou
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Zifu Zang
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
| | - Yushun Zhao
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Xiaodong He
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
| | - Chao Wang
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, China
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5
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Gissinger JR, Nikiforov I, Afshar Y, Waters B, Choi MK, Karls DS, Stukowski A, Im W, Heinz H, Kohlmeyer A, Tadmor EB. Type Label Framework for Bonded Force Fields in LAMMPS. J Phys Chem B 2024; 128:3282-3297. [PMID: 38506668 DOI: 10.1021/acs.jpcb.3c08419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
New functionality is added to the LAMMPS molecular simulation package, which increases the versatility with which LAMMPS can interface with supporting software and manipulate information associated with bonded force fields. We introduce the "type label" framework that allows atom types and their higher-order interactions (bonds, angles, dihedrals, and impropers) to be represented in terms of the standard atom type strings of a bonded force field. Type labels increase the human readability of input files, enable bonded force fields to be supported by the OpenKIM repository, simplify the creation of reaction templates for the REACTER protocol, and increase compatibility with external visualization tools, such as VMD and OVITO. An introductory primer on the forms and use of bonded force fields is provided to motivate this new functionality and serve as an entry point for LAMMPS and OpenKIM users unfamiliar with bonded force fields. The type label framework has the potential to streamline modeling workflows that use LAMMPS by increasing the portability of software, files, and scripts for preprocessing, running, and postprocessing a molecular simulation.
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Affiliation(s)
- Jacob R Gissinger
- Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, New Jersey 07030, United States
| | - Ilia Nikiforov
- Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Yaser Afshar
- Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Intel Corporation, Hillsboro, Oregon 97124, United States
| | - Brendon Waters
- Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Moon-Ki Choi
- Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Daniel S Karls
- Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | | | - Wonpil Im
- Departments of Biological Sciences, Chemistry, Bioengineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Hendrik Heinz
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, Colorado 80301, United States
| | - Axel Kohlmeyer
- Institute for Computational Molecular Science, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Ellad B Tadmor
- Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota 55455, United States
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6
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Pisani W, Wedgeworth DN, Burroughs JF, Thornell TL, Newman JK, Shukla MK. Micromechanical Dilution of PLA/PETG-Glass/Iron Nanocomposites: A More Efficient Molecular Dynamics Approach. ACS OMEGA 2024; 9:14887-14898. [PMID: 38585113 PMCID: PMC10993258 DOI: 10.1021/acsomega.3c08264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 02/23/2024] [Accepted: 03/04/2024] [Indexed: 04/09/2024]
Abstract
Polylactic acid (PLA) and poly(ethylene terephthalate glycol) (PETG) are popular thermoplastics used in additive manufacturing applications. The mechanical properties of PLA and PETG can be significantly improved by introducing fillers, such as glass and iron nanoparticles (NPs), into the polymer matrix. Molecular dynamics (MD) simulations with the reactive INTERFACE force field were used to predict the mechanical responses of neat PLA/PETG and PLA-glass/iron and PETG-glass/iron nanocomposites with relatively high loadings of glass/iron NPs. We found that the iron and glass NPs significantly increased the elastic moduli of the PLA matrix, while the PETG matrix exhibited modest increases in elastic moduli. This difference in reinforcement ability may be due to the slightly greater attraction between the glass/iron NP and PLA matrix. The NASA Multiscale Analysis Tool was used to predict the mechanical response across a range of volume percent glass/iron filler by using only the neat and highly loaded MD predictions as input. This provides a faster and more efficient approach than creating multiple MD models per volume percent per polymer/filler combination. To validate the micromechanics predictions, experimental samples incorporating hollow glass microspheres (MS) and carbonyl iron particles (CIP) into PLA/PETG were developed and tested for elastic modulus. The CIP produced a larger reinforcement in elastic modulus than the MS, with similar increases in elastic modulus between PLA/CIP and PETG/CIP at 7.77 vol % CIP. The micromechanics-based mechanical predictions compare excellently with the experimental values, validating the integrated micromechanical/MD simulation-based approach.
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Affiliation(s)
- William
A. Pisani
- Oak
Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831, United States
- Environmental
Laboratory, US Army Engineer Research and
Development Center, Vicksburg, Mississippi 39180, United States
| | - Dane N. Wedgeworth
- Geotechnical
and Structures Laboratory, US Army Engineer
Research and Development Center, Vicksburg, Mississippi 39180, United States
| | - Jedadiah F. Burroughs
- Geotechnical
and Structures Laboratory, US Army Engineer
Research and Development Center, Vicksburg, Mississippi 39180, United States
| | - Travis L. Thornell
- Geotechnical
and Structures Laboratory, US Army Engineer
Research and Development Center, Vicksburg, Mississippi 39180, United States
| | - J. Kent Newman
- Geotechnical
and Structures Laboratory, US Army Engineer
Research and Development Center, Vicksburg, Mississippi 39180, United States
| | - Manoj K. Shukla
- Environmental
Laboratory, US Army Engineer Research and
Development Center, Vicksburg, Mississippi 39180, United States
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7
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Deshpande PP, Keles O. Simulation data for engineering graphene quantum dot epoxy nanocomposites using molecular dynamics. Data Brief 2024; 53:110169. [PMID: 38389955 PMCID: PMC10881529 DOI: 10.1016/j.dib.2024.110169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/31/2024] [Accepted: 02/01/2024] [Indexed: 02/24/2024] Open
Abstract
Graphene quantum dots (GQDs) were reported to fill the role of nanofillers that enhance composite properties. Detailed investigation of this nanofiller in composites is largely unexplored. To understand the fundamental mechanisms in play, this study uses molecular dynamics simulations to reveal the effects of GQDs on epoxy properties. Mechanical simulations were performed on three varying GQD chemistries which included a pristine GQD and 2 edge aminated GQDs with different degrees of functionalization (5.2 % and 7.6 %). These GQDs were separately inserted in a polymer matrix across five individual replicates. The nanocomposite mechanical properties were computed using uniaxial strain simulations to display the effect of embedded GQDs.
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Affiliation(s)
| | - Ozgur Keles
- San Jose State University, 1 Washington Sq., San Jose, CA 95192, USA
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8
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Prasad D, Mitra N. Noncovalent Interactions in Mechanical Response of Thermoset Epoxy Resin. J Phys Chem B 2024. [PMID: 38422510 DOI: 10.1021/acs.jpcb.3c07369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Free volume in polymers is known to influence the mechanical response of the polymers. Noncovalent interactions such as hydrogen bonds, Coulombic electrostatic interactions, and van der Waals interactions are present within these free volume regions. The manuscript presents a comprehensive identification, characterization, and evolution of noncovalent interactions as a thermoset epoxy resin (typically used as an interfacial adhesive material) is subjected to uniaxial tension, shear, and shock loading. Even though noncovalent interactions dominate uniaxial tension and shear response (up to strain levels of 50% wherein covalent bond dissociation is not observed), both covalent and noncovalent interactions define response for shock loading. Van der Waals interactions dominate the response as the samples are subjected to strain levels of 50% in tension and shear. In contrast, hydrogen bonds influence shock response.
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Affiliation(s)
- Dipak Prasad
- Hopkins Extreme Materials Institute and Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Nilanjan Mitra
- Hopkins Extreme Materials Institute and Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
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9
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Hartquist CM, Lin S, Zhang JH, Wang S, Rubinstein M, Zhao X. An elastomer with ultrahigh strain-induced crystallization. SCIENCE ADVANCES 2023; 9:eadj0411. [PMID: 38091402 PMCID: PMC10848725 DOI: 10.1126/sciadv.adj0411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 11/15/2023] [Indexed: 02/12/2024]
Abstract
Strain-induced crystallization (SIC) prevalently strengthens, toughens, and enables an elastocaloric effect in elastomers. However, the crystallinity induced by mechanical stretching in common elastomers (e.g., natural rubber) is typically below 20%, and the stretchability plateaus due to trapped entanglements. We report a class of elastomers formed by end-linking and then deswelling star polymers with low defects and no trapped entanglements, which achieve strain-induced crystallinity of up to 50%. The deswollen end-linked star elastomer (DELSE) reaches an ultrahigh stretchability of 12.4 to 33.3, scaling beyond the saturated limit of common elastomers. The DELSE also exhibits a high fracture energy of 4.2 to 4.5 kJ m-2 while maintaining low hysteresis. The heightened SIC and stretchability synergistically promote a high elastocaloric effect with an adiabatic temperature change of 9.3°C.
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Affiliation(s)
- Chase M. Hartquist
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Shaoting Lin
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - James H. Zhang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Shu Wang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Michael Rubinstein
- Departments of Mechanical Engineering and Materials Science, Biomedical Engineering, Chemistry, and Physics, Duke University, Durham, NC, USA
- Institute for Chemical Reaction Design and Discovery, Hokkaido University, Sapporo, Japan
| | - Xuanhe Zhao
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
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10
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Nguyen VP, Jeon I, Yang S, Choi ST. Mesoscale Simulation of Polymer Pyrolysis by Coarse-Grained Molecular Dynamics: A Parametric Study. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37307299 DOI: 10.1021/acsami.3c04192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Full comprehension of the pyrolysis of polymer materials is crucial for the design and application of thermal protection systems; however, it involves complex phenomena at different spatial and temporal scales. To bridge the gap between the abundant atomistic simulations and continuum modeling in the literature, we perform a novel mesoscale study of the pyrolysis process using coarse-grained molecular dynamics (CG MD) simulations. Polyethylene (PE) consisting of united atoms including implicit hydrogen is considered a model polymer, and the configurational change of PE in thermal degradation is modeled by applying the bond-breaking phenomenon based on bond energy or bond length criteria. A cook-off simulation is implemented to optimize the heuristic protocol of bond dissociation by comparing the reaction products with a ReaxFF simulation. The aerobic hyperthermal pyrolysis under oxygen bombardment is simulated at a large scale of hundreds of nanometers to observe the intricate phenomena occurring from the surface to the depth inside the material. The intrinsic thermal durability of the model polymer at extreme conditions with and without oxygen environment can be effectively simulated from the proposed mesoscale simulation to predict important thermal degradation properties required for continuum-scale pyrolysis and ablation simulations. This work serves as an initial investigation of polymer pyrolysis at the mesoscale and helps understand the concept at a larger scale.
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Affiliation(s)
- Vinh Phu Nguyen
- Functional Materials and Applied Mechanics Lab, School of Mechanical Engineering, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul 06974, Republic of Korea
| | - Inseok Jeon
- Mechanical Energy Engineering Division, School of Energy Systems Engineering, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul 06974, Republic of Korea
| | - Seunghwa Yang
- Mechanical Energy Engineering Division, School of Energy Systems Engineering, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul 06974, Republic of Korea
| | - Seung Tae Choi
- Functional Materials and Applied Mechanics Lab, School of Mechanical Engineering, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul 06974, Republic of Korea
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11
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Karnes JJ, Weisgraber TH, Cook CC, Wang DN, Crowhurst JC, Fox CA, Harris BS, Oakdale JS, Faller R, Shusteff M. Isolating Chemical Reaction Mechanism as a Variable with Reactive Coarse-Grained Molecular Dynamics: Step-Growth versus Chain-Growth Polymerization. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Affiliation(s)
- John J. Karnes
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
| | - Todd H. Weisgraber
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
| | - Caitlyn C. Cook
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
| | - Daniel N. Wang
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
| | | | - Christina A. Fox
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
- Department of Materials Science and Engineering, University of California, Davis, Davis, California 95616, United States
| | - Bradley S. Harris
- Department of Chemical Engineering, University of California, Davis, Davis, California 95616, United States
| | - James S. Oakdale
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
| | - Roland Faller
- Department of Chemical Engineering, University of California, Davis, Davis, California 95616, United States
| | - Maxim Shusteff
- Lawrence Livermore National Laboratory Livermore, California 94550, United States
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12
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Schöller L, Nestler B, Denniston C. Modeling of a two-stage polymerization considering glass fibre sizing using molecular dynamics. NANOSCALE ADVANCES 2022; 5:106-118. [PMID: 36605801 PMCID: PMC9765651 DOI: 10.1039/d2na00562j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
Fibre reinforced polymers are an important class of materials due to their light weight, high strength, and stiffness. However, there is a lack of knowledge about the interaction of fibre surface, sizing (fibre coating), and resin. Often only idealised academic systems are studied, and only rarely realistic systems that are used in an industrial context. Therefore, methods for studying the behaviour of complex sizing are highly desirable, especially as they play a crucial role in the performance of fibre reinforced polymers. Here, a simplified, yet industrially used resin system is extended using molecular dynamics simulations by adding a fibre surface and sizing layers. Furthermore, a common coupling agent was selected, and several additional assumptions were made about the structure of the sizing. Based on this, a systematic procedure for the development of a final cured system is introduced: a condensation reaction to form oligomers from coupling agent monomers is conducted. Subsequently, a two stage reaction, a polyurethane reaction and a radical polymerisation, is modelled based on an established approach. Using the final cured system, evaluations of averaged quantities during the reactions are carried out. Moreover, the system is evaluated along the normal direction of the fibre surface, which proves a spatial analysis of the fibre-sizing-resin interface.
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Affiliation(s)
- Lukas Schöller
- Institute for Applied Materials (IAM-MMS), Karlsruhe Institute of Technology (KIT) Kaiserstrasse 12 76131 Karlsruhe Germany
- Institute of Digital Materials Science (IDM), Karlsruhe University of Applied Sciences Moltkestrasse 30 76133 Karlsruhe Germany
| | - Britta Nestler
- Institute for Applied Materials (IAM-MMS), Karlsruhe Institute of Technology (KIT) Kaiserstrasse 12 76131 Karlsruhe Germany
- Institute of Digital Materials Science (IDM), Karlsruhe University of Applied Sciences Moltkestrasse 30 76133 Karlsruhe Germany
| | - Colin Denniston
- Department of Physics & Astronomy, University of Western Ontario (UWO) 1151 Richmond Street London ON N6A 3K7 Canada
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13
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Simulating Polymerization by Boltzmann Inversion Force Field Approach and Dynamical Nonequilibrium Reactive Molecular Dynamics. Polymers (Basel) 2022; 14:polym14214529. [DOI: 10.3390/polym14214529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/19/2022] [Accepted: 10/21/2022] [Indexed: 11/16/2022] Open
Abstract
The radical polymerization process of acrylate compounds is, nowadays, numerically investigated using classical force fields and reactive molecular dynamics, with the aim to probe the gel-point transition as a function of the initial radical concentration. In the present paper, the gel-point transition of the 1,6-hexanediol dimethacrylate (HDDMA) is investigated by a coarser force field which grants a reduction in the computational costs, thereby allowing the simulation of larger system sizes and smaller radical concentrations. Hence, the polymerization is investigated using reactive classical molecular dynamics combined with a dynamical approach of the nonequilibrium molecular dynamics (D-NEMD). The network structures in the polymerization process are probed by cluster analysis tools, and the results are critically compared with the similar all-atom system, showing a good agreement.
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14
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Orselly M, Devemy J, Bouvet-Marchand A, Dequidt A, Loubat C, Malfreyt P. Molecular Simulations of Thermomechanical Properties of Epoxy-Amine Resins. ACS OMEGA 2022; 7:30040-30050. [PMID: 36061676 PMCID: PMC9434774 DOI: 10.1021/acsomega.2c03071] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/01/2022] [Indexed: 06/15/2023]
Abstract
All-atom molecular dynamics (MD) simulations were performed with the CHARMM force field to characterize various epoxy resins, such as aliphatic and bisphenol-based resins. A multistep cross-linking algorithm was established, and key properties such as density, glass temperature, and elastic modulus were calculated. A quantitative comparison was made and was proven to be in good agreement with experimental data, with average absolute deviations between experiments and molecular simulation comprised between 2% and 12%. Additional findings on structure-property relationships were highlighted such as the effect of the cross-linking rate and oligomerization of the resin.
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Affiliation(s)
- Mathilde Orselly
- Specific
Polymers, 150 Avenue des Cocardières, 34160 Castries, France
- Université
Clermont Auvergne,Clermont Auvergne
INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Julien Devemy
- Université
Clermont Auvergne,Clermont Auvergne
INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | | | - Alain Dequidt
- Université
Clermont Auvergne,Clermont Auvergne
INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Cédric Loubat
- Specific
Polymers, 150 Avenue des Cocardières, 34160 Castries, France
| | - Patrice Malfreyt
- Université
Clermont Auvergne,Clermont Auvergne
INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
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15
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Zhang Y, Yang H, Sun Y, Zheng X, Guo Y. A molecular dynamics simulation on tunable and self-healing epoxy-polyimine network based on imine bond exchange reactions. MOLECULAR SIMULATION 2022. [DOI: 10.1080/08927022.2022.2110601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Affiliation(s)
- Yongqin Zhang
- Department of Mechanics, School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, People’s Republic of China
| | - Hua Yang
- School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, People’s Republic of China
| | - Yaguang Sun
- Department of Mechanics, School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, People’s Republic of China
| | - Xiangrui Zheng
- Department of Mechanics, School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, People’s Republic of China
| | - Yafang Guo
- Department of Mechanics, School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, People’s Republic of China
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16
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Jull EIL, Mandle RJ, Raistrick T, Zhang Z, Hine PJ, Gleeson HF. Toward In Silico Design of Highly Tunable Liquid Crystal Elastomers. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00587] [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)
- Ethan I. L. Jull
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - Richard J. Mandle
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - Thomas Raistrick
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - Zhaopeng Zhang
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - Peter J. Hine
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - Helen F. Gleeson
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
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17
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Zhao Y, Kikugawa G, Kawagoe Y, Shirasu K, Kishimoto N, Xi Y, Okabe T. Uncovering the Mechanism of Size Effect on the Thermomechanical Properties of Highly Cross-Linked Epoxy Resins. J Phys Chem B 2022; 126:2593-2607. [PMID: 35325528 DOI: 10.1021/acs.jpcb.1c10827] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Epoxy resins are widely used as matrix resins, especially for carbon-fiber-reinforced plastic, due to their outstanding physical and mechanical properties. To date, most research into cross-linking processes using simulation has considered only a distance-based criterion to judge the probability of reaction. In this work, a new algorithm was developed for use with the large-scale atomic/molecular massively parallel simulator (LAMMPS) simulation package to study the cross-linking process; this new approach combines both a distance-based criterion and several kinetic criteria to identify whether the reaction has occurred. Using this simulation framework, we investigated the effect of model size on predicted thermomechanical properties of three different structural systems: diglycidyl ether of bisphenol A (DGEBA)/4,4'-diaminodiphenyl sulfone (4,4'-DDS), DGEBA/diethylenetriamine (DETA), and tetraglycidyl diaminodiphenylmethane (TGDDM)/4,4'-DDS. Derived values of gel point, volume shrinkage, and cross-linked resin density were found to be insensitive to model size in these three systems. Other thermomechanical properties, i.e., glass-transition temperature, Young's modulus, and yield stress, were found to reach stable values for systems larger than ∼40 000 atoms for both DGEBA/4,4'-DDS and DGEBA/DETA. However, these same properties modeled for TGDDM/4,4'-DDS did not stabilize until the system size reached 50 000 atoms. Our results provide general guidelines for simulation system size and procedures to more accurately predict the thermomechanical properties of epoxy resins.
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Affiliation(s)
- Yinbo Zhao
- Department of Aerospace Engineering, Tohoku University, 6-6-01, Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan.,Institute of Fluid Science, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Gota Kikugawa
- Institute of Fluid Science, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Yoshiaki Kawagoe
- Department of Aerospace Engineering, Tohoku University, 6-6-01, Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Keiichi Shirasu
- Department of Aerospace Engineering, Tohoku University, 6-6-01, Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Naoki Kishimoto
- Department of Chemistry, Tohoku University, 6-3 Aramaki Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
| | - Yingxiao Xi
- Department of Chemistry, Tohoku University, 6-3 Aramaki Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
| | - Tomonaga Okabe
- Department of Aerospace Engineering, Tohoku University, 6-6-01, Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan.,Department of Materials Science and Engineering, University of Washington, Box 352120, Seattle, Washington 98195, United States.,Research Center for Structural Materials, Polymer Matrix Hybrid Composite Materials Group, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
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18
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Monteferrante M, Tiribocchi A, Succi S, Pisignano D, Lauricella M. Capturing Free-Radical Polymerization by Synergetic Ab Initio Calculations and Topological Reactive Molecular Dynamics. Macromolecules 2022; 55:1474-1486. [PMID: 35287293 PMCID: PMC8909409 DOI: 10.1021/acs.macromol.1c01408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/08/2021] [Indexed: 11/30/2022]
Abstract
Photocurable polymers are used ubiquitously in 3D printing, coatings, adhesives, and composite fillers. In the present work, the free radical polymerization of photocurable compounds is studied using reactive classical molecular dynamics combined with a dynamical approach of the nonequilibrium molecular dynamics (D-NEMD). Different concentrations of radicals and reaction velocities are considered. The mechanical properties of the polymer resulting from 1,6-hexanediol dimethacrylate systems are characterized in terms of viscosity, diffusion constant, and activation energy, whereas the topological ones through the number of cycles (polymer loops) and cyclomatic complexity. Effects like volume shrinkage and delaying of the gel point for increasing monomer concentration are also predicted, as well as the stress-strain curve and Young's modulus. Combining ab initio, reactive molecular dynamics, and the D-NEMD method might lead to a novel and powerful tool to describe photopolymerization processes and to original routes to optimize additive manufacturing methods relying on photosensitive macromolecular systems.
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Affiliation(s)
| | - Adriano Tiribocchi
- Istituto
per le Applicazioni del Calcolo CNR, Via dei Taurini 19, 00185 Rome, Italy
| | - Sauro Succi
- Istituto
per le Applicazioni del Calcolo CNR, Via dei Taurini 19, 00185 Rome, Italy,Center
for Life Nano Science@La Sapienza, Istituto
Italiano di Tecnologia, Viale Regina Elena, 291, 00161 Rome, Italy
| | - Dario Pisignano
- Dipartimento
di Fisica, Università di Pisa, Largo B. Pontecorvo 16 3, 56127 Pisa, Italy,NEST,
Istituto Nanoscienze-CNR, Piazza S. Silvestro 12, 56127 Pisa, Italy
| | - Marco Lauricella
- Istituto
per le Applicazioni del Calcolo CNR, Via dei Taurini 19, 00185 Rome, Italy,
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19
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Vickers R, Weigand TM, Miller CT, Coronell O. Molecular Methods for Assessing the Morphology, Topology, and Performance of Polyamide Membranes. J Memb Sci 2022; 644:120110. [PMID: 35082452 PMCID: PMC8786217 DOI: 10.1016/j.memsci.2021.120110] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The molecular-scale morphology and topology of polyamide composite membranes determine the performance characteristics of these materials. However, molecular-scale simulations are computationally expensive and morphological and topological characterization of molecular structures are not well developed. Molecular dynamics simulation and analysis methods for the polymerization, hydration, and quantification of polyamide membrane structures were developed and compared to elucidate efficient approaches for producing and analyzing the polyamide structure. Polymerization simulations that omitted the reaction-phase solvent did not change the observed hydration, pore-size distribution, or water permeability, while improving the simulation efficiency. Pre-insertion of water into the aggregate pores (radius ≈ 4 Å) of dry domains enabled shorter hydration simulations and improved simulation scaling, without altering pore structure, properties, or performance. Medial axis and Minkowski functional methods were implemented to identify permeation pathways and quantify the polyamide morphology and topology, respectively. Better agreement between simulations and experimentally observed systems was accomplished by increasing the domain size rather than increasing the number of ensemble realizations of smaller systems. The largest domain hydrated was an order of magnitude larger by volume than the largest domain previously reported. This work identifies methods that can enable more efficient and meaningful fundamental modeling of membrane materials.
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Affiliation(s)
- Riley Vickers
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431, USA
| | - Timothy M. Weigand
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431, USA
| | - Cass T. Miller
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431, USA
| | - Orlando Coronell
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431, USA
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20
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Yeganeh MS, Jusufi A, Deighton SP, Ide MS, Siskin M, Jaishankar A, Maldarelli C, Bertolini P, Natarajan B, Vreeland JL, King MA, Konicek AR. Solid with infused reactive liquid (SWIRL): A novel liquid-based separation approach for effective CO 2 capture. SCIENCE ADVANCES 2022; 8:eabm0144. [PMID: 35138903 PMCID: PMC8827647 DOI: 10.1126/sciadv.abm0144] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
Economical CO2 capture demands low-energy separation strategies. We use a liquid-infused surface (LIS) approach to immobilize reactive liquids, such as amines, on a textured and thermally conductive solid substrate with high surface-area to volume ratio (A/V) continuum geometry. The infused, micrometer-thick liquid retains that high A/V and directly contacts the gas phase, alleviating mass transport resistance typically encountered in mesoporous solid adsorbents. We name this LIS class "solid with infused reactive liquid" (SWIRL). SWIRL-amine requires no water dilution or costly mixing unlike the current liquid-based commercial approach. SWIRL-tetraethylenepentamine (TEPA) shows stable, high capture capacities at power plant CO2 concentrations near flue gas temperatures, preventing energy-intensive temperature swings needed for other approaches. Water vapor increases CO2 capacity of SWIRL-TEPA without compromising stability.
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Affiliation(s)
- Mohsen S. Yeganeh
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Arben Jusufi
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Shane P. Deighton
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Matthew S. Ide
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Michael Siskin
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Aditya Jaishankar
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Charles Maldarelli
- Chemical Engineering, The City College of New York, New York, NY 10031, USA
| | - Pedro Bertolini
- Chemical Engineering, The City College of New York, New York, NY 10031, USA
| | - Bharath Natarajan
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | | | - Mark A. King
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
| | - Andrew R. Konicek
- ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
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21
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Abbott JW, Hanke F. Kinetically Corrected Monte Carlo-Molecular Dynamics Simulations of Solid Electrolyte Interphase Growth. J Chem Theory Comput 2022; 18:925-934. [PMID: 35007421 DOI: 10.1021/acs.jctc.1c00921] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present a kinetic approach to the Monte Carlo-molecular dynamics (MC-MD) method for simulating reactive liquids using nonreactive force fields. A graphical reaction representation allows definition of reactions of arbitrary complexity, including their local solvation environment. Reaction probabilities and molecular dynamics (MD) simulation times are derived from ab initio calculations. Detailed validation is followed by studying the development of the solid electrolyte interphase (SEI) in lithium-ion batteries. We reproduce the experimentally observed two-layered structure on graphite, with an inorganic layer close to the anode and an outer organic layer. This structure develops via a near-shore aggregation mechanism.
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22
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Zeidi M, Kim CI, Park CB. The role of interface on the toughening and failure mechanisms of thermoplastic nanocomposites reinforced with nanofibrillated rubber. NANOSCALE 2021; 13:20248-20280. [PMID: 34851346 DOI: 10.1039/d1nr07363j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The interface plays a crucial role in the physical and functional properties of polymer nanocomposites, yet its effects have not been fully recognized in the setting of classical continuum-based modeling. In the present study, we investigate the roles of interface and interfiber interactions on the toughening effects of rubber nanofibers embodied in thermoplastic-based materials. Emphasis is placed on establishing comprehensive theoretical and atomistic descriptions of the nanocomposite systems subjected to pull-out and uniaxial extension in the longitudinal and transverse directions. Using the framework of molecular dynamics, the annealed melt-drawn nanofibers were spontaneously formed via the proposed four-step methodology. The generated nanofibers were then crosslinked using the proposed robust topology-matching algorithm, through which the chemical reactions arising in the crosslinking were closely assimilated. The interfiber interactions were also examined with respect to separation distances and nanofiber radius via a nanofiber-pair atomistic scheme, and the obtained results were subsequently incorporated into the pull-out and uniaxial test simulations. The results indicate that the compatibilizer grafting results in enhanced interfacial shear strength by introducing extra chemical interactions at the interface. In particular, it was found that the compatibilizer restricts the formation and coalescence of nanovoids, resulting in enhanced toughening effects. Together, we have shown that the presence of a small amount of well-dispersed rubber nanofibrillar network whose surfaces are grafted with maleic anhydride compatibilizer can dramatically increase the toughness and alter the failure mechanisms of the nanocomposites without any deterioration in the stiffness, which is also consistent with the recent experimental observations in our lab. The interfacial failure mechanism was also investigated by monitoring the changes in the atomic concentration profiles, mean square displacement and fractional free volume. The results obtained may serve as a promising alternative for the continuum-based modeling and analysis of interfaces.
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Affiliation(s)
- Mahdi Zeidi
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON, Canada M5S 3G8.
| | - Chun Il Kim
- Department of Mechanical Engineering, University of Alberta, 9211 116 Street NW, Edmonton, AB, Canada T6G 1H9.
| | - Chul B Park
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON, Canada M5S 3G8.
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23
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Affiliation(s)
- Guido Raos
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via L. Mancinelli 7, I-20131 Milano, Italy
| | - Bruno Zappone
- Consiglio Nazionale delle Ricerche - Istituto di Nanotecnologia (CNR-Nanotec), Via P. Bucci, 33/C, 87036 Rende (CS), Italy
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24
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Yan S, Verestek W, Zeizinger H, Schmauder S. Characterization of Cure Behavior in Epoxy Using Molecular Dynamics Simulation Compared with Dielectric Analysis and DSC. Polymers (Basel) 2021; 13:polym13183085. [PMID: 34577986 PMCID: PMC8469284 DOI: 10.3390/polym13183085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/03/2021] [Accepted: 09/10/2021] [Indexed: 01/25/2023] Open
Abstract
The curing behavior of a thermosetting material that influences the properties of the material is a key issue for predicting the changes in material properties during processing. An empirical equation can describe the reaction kinetics of the curing behavior of an investigated material, which is usually estimated using experimental methods. In this study, the curing process of an epoxy resin, the polymer matrix in an epoxy molding compound, is computed concerning thermal influence using molecular dynamics. Furthermore, the accelerated reaction kinetics, which are influenced by an increased reaction cutoff distance, are investigated. As a result, the simulated crosslink density with various cutoff distances increases to plateau at a crosslink density of approx. 90% for the investigated temperatures during curing time. The reaction kinetics are derived according to the numerical results and compared with the results using experimental methods (dielectric analysis and differential scanning calorimetry), whereby the comparison shows a good agreement between experiment and simulation.
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25
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Kawagoe Y, Kikugawa G, Shirasu K, Okabe T. Thermoset resin curing simulation using quantum-chemical reaction path calculation and dissipative particle dynamics. SOFT MATTER 2021; 17:6707-6717. [PMID: 34169305 DOI: 10.1039/d1sm00600b] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Thermoset resin, which is commonly used as a matrix in carbon-fiber-reinforced plastic, requires curing procedures. We propose a curing simulation technique involving a dissipative particle dynamics (DPD) simulation, which can simulate a larger system and longer time period than those of conventional all-atom molecular dynamics (AA-MD) simulations. The proposed curing DPD simulation can represent the thermoset resin exothermic reaction process precisely by considering each reactivity according to the reaction types calculated via quantum-chemical reaction path calculations. The cure reaction process given by the curing DPD simulation agrees well with that given by a conventional curing AA-MD simulation, but with run-time and computational-resource reductions of 1/480 and 1/10 times, respectively. We also conduct reverse mapping, through which the AA-MD system can be reconstructed from the DPD system, to evaluate the structural and thermomechanical properties. The X-ray diffraction pattern and thermomechanical properties of the reconstructed system agree well with those of the systems derived from the curing AA-MD simulation and experimental setup. Therefore, a cured-resin AA-MD system can be obtained from a curing DPD simulation at an extremely low computational cost, and the thermomechanical properties can be evaluated precisely using this system. The proposed curing simulation technique can be applied in high-throughput screening for better materials properties and in large system calculations.
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Affiliation(s)
- Yoshiaki Kawagoe
- Department of Aerospace Engineering, Tohoku University, Sendai 980-8579, Japan.
| | - Gota Kikugawa
- Institute of Fluid Science, Tohoku University, Sendai 980-8577, Japan.
| | - Keiichi Shirasu
- Department of Aerospace Engineering, Tohoku University, Sendai 980-8579, Japan.
| | - Tomonaga Okabe
- Department of Aerospace Engineering, Tohoku University, Sendai 980-8579, Japan. and Department of Materials Science and Engineering, University of Washington, Seattle, Washington, USA
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26
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Yamamoto S, Kuwahara R, Tanaka K. Dynamic behaviour of water molecules in heterogeneous free space formed in an epoxy resin. SOFT MATTER 2021; 17:6073-6080. [PMID: 34132297 DOI: 10.1039/d1sm00529d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Although an epoxy resin is a stable material, it absorbs moisture over a long period of time, causing deterioration of its material properties. We here applied a full-atomistic molecular dynamics (MD) simulation to study where water molecules exist in an epoxy resin and how they dynamically behave. First, the curing reaction was simulated to obtain a network structure so that the time course of the density, and thereby the free space, in the resin were obtained. The results made it possible to discuss the formation and size distribution of the free spaces which were not connected to each other. Then, a few percent of water were inserted into the free space of the cured epoxy resin to examine the location and dynamics of their molecules. We found that several water molecules were clustered at a preferred site, where hydrogen bonds can be formed with hydroxy, ether and amino groups of the network, in the free space, and they heterogeneously moved from there to other sites.
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Affiliation(s)
- Satoru Yamamoto
- Centre for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan.
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27
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Tow GM, Maginn EJ. Cross-Linking Methodology for Fully Atomistic Models of Hydroxyl-Terminated Polybutadiene and Determination of Mechanical Properties. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00228] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Garrett M. Tow
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Edward J. Maginn
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
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