1
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Xu T, Cui K, Nie C, Peng F, Cao R, Liu Z, Sun H, Li L. Bond Orientation-Determined Enthalpic Stress in Polymer Glasses upon Deformation. ACS Macro Lett 2023; 12:1251-1256. [PMID: 37643284 DOI: 10.1021/acsmacrolett.3c00387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The mechanical properties of polymer glass are determined by both intermolecular local packing structures and aligned intrachain configurations. These configurations involve multiple space scales, and the underlying mechanism is not well understood yet. By applying mechanical stimulation to cold-drawn polymer glasses, the present simulation work shows a one-to-one correspondence between arising retractive stress and the segment orientation parameter on the length scale of the intrachain connecting bond. Such retractive stress is a newly produced enthalpic stress when segment orientation on the length scale of bonds and particle mobility coexist. This reveals a potential mechanism of how the intrachain orientation on the length scale of bonds influences the mechanical behaviors of polymer glasses.
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Affiliation(s)
- Tingyu Xu
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Kunpeng Cui
- Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Cui Nie
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Fan Peng
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Renkuan Cao
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Ziwei Liu
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Hao Sun
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Liangbin Li
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
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2
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Hem J, Crauste-Thibierge C, Merlette TC, Clément F, Long DR, Ciliberto S. Microscopic Dynamics in the Strain Hardening Regime of Glassy Polymers. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00802] [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)
- Jérôme Hem
- ENS de Lyon, CNRS, Laboratoire de physique, F-69342 Lyon, France
| | | | - Thomas C. Merlette
- CNRS/Solvay, UMR 5268, Laboratoire Polymères et Matériaux Avancés, 87 avenue des Frères Perret, 69192 Cedex Saint Fons, France
| | - Florence Clément
- CNRS/Solvay, UMR 5268, Laboratoire Polymères et Matériaux Avancés, 87 avenue des Frères Perret, 69192 Cedex Saint Fons, France
| | - Didier R. Long
- CNRS/Solvay, UMR 5268, Laboratoire Polymères et Matériaux Avancés, 87 avenue des Frères Perret, 69192 Cedex Saint Fons, France
- CNRS, INSA Lyon, MATEIS, UMR5510, Univ. Lyon, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France
| | - Sergio Ciliberto
- ENS de Lyon, CNRS, Laboratoire de physique, F-69342 Lyon, France
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3
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Xing E, Bennin T, Razavi M, Ediger MD. Segmental Dynamics in the Strain-Hardening Regime for Poly(methyl methacrylate) Glasses with and without Melt Stretching. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Enran Xing
- Department of Chemistry, University of Wisconsin − Madison, Madison, Wisconsin 53706, United States
| | - Trevor Bennin
- Department of Chemistry, University of Wisconsin − Madison, Madison, Wisconsin 53706, United States
| | - Masoud Razavi
- Department of Chemistry, University of Wisconsin − Madison, Madison, Wisconsin 53706, United States
| | - Mark D. Ediger
- Department of Chemistry, University of Wisconsin − Madison, Madison, Wisconsin 53706, United States
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4
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Optimal Entanglement of Polymers Promotes the Formation of Highly Oriented Fibers. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00578] [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]
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5
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Maurya MK, Ruscher C, Mukherji D, Singh MK. Computational indentation in highly cross-linked polymer networks. Phys Rev E 2022; 106:014501. [PMID: 35974630 DOI: 10.1103/physreve.106.014501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Indentation is a common experimental technique to study the mechanics of polymeric materials. The main advantage of using indentation is this provides a direct correlation between the microstructure and the small-scale mechanical response, which is otherwise difficult within the standard tensile testing. The majority of studies have investigated hydrogels, microgels, elastomers, and even soft biomaterials. However, a less investigated system is the indentation in highly cross-linked polymer (HCP) networks, where the complex network structure plays a key role in dictating their physical properties. In this work, we investigate the structure-property relationship in HCP networks using the computational indentation of a generic model. We establish a correlation between the local bond breaking, network rearrangement, and small-scale mechanics. The results are compared with the elastic-plastic deformation model. HCPs harden upon indentation.
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Affiliation(s)
- Manoj Kumar Maurya
- Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur UP 208016, India
| | - Céline Ruscher
- Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada BC V6T 1Z4
| | - Debashish Mukherji
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada BC V6T 1Z4
| | - Manjesh Kumar Singh
- Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur UP 208016, India
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6
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Xu T, Nie C, Peng F, Sheng J, Li L. Bond Orientation-Assisted Enthalpic Stress in Polymer Glasses: A Simulation Study on Elastic Yielding. Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c02124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tingyu Xu
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Cui Nie
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Fan Peng
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Junfang Sheng
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Liangbin Li
- National Synchrotron Radiation Lab, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China
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7
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Abnormal brittle-ductile transition for glassy polymers after free and constrained melt stretching: The role of molecular alignment. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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8
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Bukowski C, Zhang T, Riggleman RA, Crosby AJ. Load-bearing entanglements in polymer glasses. SCIENCE ADVANCES 2021; 7:eabg9763. [PMID: 34533993 PMCID: PMC8448454 DOI: 10.1126/sciadv.abg9763] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 07/29/2021] [Indexed: 06/13/2023]
Abstract
Through a combined approach of experiment and simulation, this study quantifies the role of entanglements in determining the mechanical properties of glassy polymer blends. Uniaxial extension experiments on 100-nm films containing a bidisperse mixture of polystyrene enable quantitative comparison with molecular dynamics (MD) simulations of a coarse-grained model for polymer glasses, where the bidisperse blends allow us to systematically tune the entanglement density of both systems. In the MD simulations, we demonstrate that not all entanglements carry substantial load at large deformation, and our analysis allows the development of a model to describe the number of effective, load-bearing entanglements per chain as a function of blend ratio. The film strength measured experimentally and the simulated film toughness are quantitatively described by a model that only accounts for load-bearing entanglements.
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Affiliation(s)
- Cynthia Bukowski
- Polymer Science and Engineering Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Tianren Zhang
- Chemical and Biomolecular Engineering Department, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert A. Riggleman
- Chemical and Biomolecular Engineering Department, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alfred J. Crosby
- Polymer Science and Engineering Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
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9
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Nan K, Abritta P, Hoy RS. How Does the Character of Glassy-Polymeric Cavitation Depend on Entanglement Density and the Local Poisson Ratio? Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01128] [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)
- Kai Nan
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Pedro Abritta
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Robert S. Hoy
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
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10
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Ge T, Wang J, Robbins MO. Effects of Coarse-Graining on Molecular Simulations of Mechanical Properties of Glassy Polymers. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02467] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ting Ge
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Jiuling Wang
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Mark O. Robbins
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
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11
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Kwon T, Sung BJ. Confinement effects on the mechanical heterogeneity of polymer fiber glasses. Phys Rev E 2020; 102:052501. [PMID: 33327119 DOI: 10.1103/physreve.102.052501] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/13/2020] [Indexed: 11/07/2022]
Abstract
Both polymer fiber glasses and bulk polymer glasses exhibit nonlinear mechanical responses under uniaxial deformation. In polymer fibers, however, polymer chains are confined strongly and the surface area is relatively large compared to their volume. The confinement and the surface may lead to the spatially heterogeneous relaxation of chains in polymer fibers. In this work we perform molecular dynamics simulations and investigate the relation between the heterogeneous dynamics and the nonlinear mechanical responses at a molecular level. Our molecular simulations capture successfully not only the nonlinear mechanical response but also the dependence of mechanical properties on the strain rate of typical polymer glasses as in experiments. We find that the local elastic modulus and the nonaffine displacement are spatially heterogeneous in the pre-yield regime, which results in a lower elastic modulus for polymer fibers than bulk polymer glasses. In the post-yield regime, those mechanical properties become relatively homogeneous. Monomers with large nonaffine displacement are localized mainly at the interfacial region in the pre-yield regime while highly nonaffine monomers are distributed throughout the fibers in the post-yield regime. We show that the nonaffine displacement during deformation relates closely to the mechanical response of the polymer fibers. We also find that in the strain-hardening regime there is a significant difference in the energetic contribution to the stress between polymer fibers and bulk polymers, for which the modulus of the strain-hardening regime of the polymer fibers is smaller than that of bulk polymers.
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Affiliation(s)
- Taejin Kwon
- Department of Chemistry, Sogang University, Seoul 04107, Republic of Korea
| | - Bong June Sung
- Department of Chemistry, Sogang University, Seoul 04107, Republic of Korea
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12
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Djukic S, Bocahut A, Bikard J, Long DR. Study of Damage Mechanisms of Amorphous and Low Semicrystalline Polymers under Tensile Deformation by Ultrasmall-Angle X-ray Scattering. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00534] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stéphanie Djukic
- LPMA, Laboratoire des polymères et Matériaux Avancés, UMR 5268 Solvay/CNRS, Solvay in Axel’One, 87 avenue des Frères Perret CS 70061, 69192 St-Fons Cedex, France
| | - Anthony Bocahut
- Solvay Research and Innovation Center, 87 avenue des Frères Perret, 69192 St-Fons Cedex, France
| | - Jérôme Bikard
- Solvay Research and Innovation Center, 87 avenue des Frères Perret, 69192 St-Fons Cedex, France
| | - Didier R. Long
- LPMA, Laboratoire des polymères et Matériaux Avancés, UMR 5268 Solvay/CNRS, Solvay in Axel’One, 87 avenue des Frères Perret CS 70061, 69192 St-Fons Cedex, France
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13
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Jabbari-Farouji S, Vandembroucq D. Compression-induced anti-nematic order in glassy and semicrystalline polymers. SOFT MATTER 2020; 16:102-106. [PMID: 31793978 DOI: 10.1039/c9sm01848d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We provide new insights into the molecular origin of the asymmetry between uniaxial tensile and compressive deformation of glassy and semicrystalline polymers using molecular dynamics simulations. The difference between the two responses strongly depends on the chain length and is the largest at intermediate chain lengths. Irrespective of chain length, the intra- and interchain organization of polymers under extension and compression are remarkably distinct. The chains align along the tensile axis leading to a global nematic order of the bonds and end-to-end vectors, whereas compression reorganizes polymers to lie in planes perpendicular to the compressive axis resulting in the emergence of an anti-nematic order and destruction of crystallinity. Regardless of the initial glassy or semicrystalline structure, the deformed state of polymers at large strains converge towards the same kind of structure that only depends on the deformation mode.
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Affiliation(s)
- Sara Jabbari-Farouji
- Institute of Physics, Johannes Gutenberg-University, Staudingerweg 7-9, 55128 Mainz, Germany and Institute of Physics, University of Amsterdam, 1098 XH Amsterdam, The Netherlands.
| | - Damien Vandembroucq
- Laboratoire PMMH, UMR 7636 CNRS, ESPCI, PSL Research University, Sorbonne Université, Université Paris Diderot, Paris, France
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14
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Zou W, Moghadam S, Hoy RS, Larson RG. Multiscale Modeling of Sub-Entanglement-Scale Chain Stretching and Strain Hardening in Deformed Polymeric Glasses. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00901] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Weizhong Zou
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Soroush Moghadam
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Robert S. Hoy
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Ronald G. Larson
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
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15
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O’Connor TC, Hopkins A, Robbins MO. Stress Relaxation in Highly Oriented Melts of Entangled Polymers. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01161] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Thomas C. O’Connor
- Sandia National Laboratories, Albuquerque, New Mexico 87123, United States
| | - Austin Hopkins
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Mark O. Robbins
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
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16
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Elzière P, Fourton P, Demassieux Q, Chennevière A, Dalle-Ferrier C, Creton C, Ciccotti M, Barthel E. Supramolecular Structure for Large Strain Dissipation and Outstanding Impact Resistance in Polyvinylbutyral. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01277] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Paul Elzière
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France
- Saint-Gobain Recherche, 39 Quai Lucien Lefranc, 93300 Aubervilliers, France
| | - Paul Fourton
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France
- Saint-Gobain Recherche, 39 Quai Lucien Lefranc, 93300 Aubervilliers, France
| | - Quentin Demassieux
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France
| | | | | | - Costantino Creton
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Matteo Ciccotti
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Etienne Barthel
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France
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17
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Zhao Z, Zhao X, Liu J, Wang W, Mays J, Wang SQ. Characterizing effects of fast melt deformation on entangled polymers in their glassy state. J Chem Phys 2019; 151:124906. [PMID: 31575207 DOI: 10.1063/1.5111876] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Fast deformation of entangled melts is known to cause chain stretching due to affinelike straining of the entanglement network. Since the chain deformation may also result in perturbations of covalent bond angles and bond length, there are always possible enthalpic effects. In this study, we first subject polystyrene and PMMA of different molecular weights to either uniaxial melt extension or planar extension and subsequently impose rapid thermal quenching to preserve the chain deformation. Then, such pre-melt-deformed samples are annealed at various temperatures below the glass transition temperature Tg. During annealing, these samples can undergo appreciable contraction on a time scale much shorter than the alpha relaxation time. Significant retractive stress is observed when such contracting samples are held fixed during the annealing. The stress level can be nearly as high as the Cauchy stress produced during melt stretching. These observations not only allowed us to investigate glassy chain dynamics as well as the molecular nature of mechanical stress but may also suggest that pre-melt-stretched polymers can cause segmental mobilization in the glassy state. The available evidence indicates that the retractive stress is enthalpic in origin, associated with the conformational distortion at the bond level produced by melt stretching.
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Affiliation(s)
- Zhichen Zhao
- Department of Polymer Science, University of Akron, Akron, Ohio 44325, USA
| | - Xinyang Zhao
- Department of Chemistry, Jiao Tong University, Shanghai, China
| | - Jianning Liu
- Department of Polymer Science, University of Akron, Akron, Ohio 44325, USA
| | - Weiyu Wang
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Jimmy Mays
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Shi-Qing Wang
- Department of Polymer Science, University of Akron, Akron, Ohio 44325, USA
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18
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All-atom molecular dynamics study of impact fracture of glassy polymers. I: Molecular mechanism of brittleness of PMMA and ductility of PC. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.121570] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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19
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Charvet A, Vergelati C, Sotta P, Long DR. Damage Mechanisms of Plasticized Cellulose Acetate under Tensile Deformation Studied by Ultrasmall-Angle X-ray Scattering. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00858] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Agathe Charvet
- Laboratoire des polymères et Matériaux Avancés, UMR 5268 Solvay/CNRS, Solvay in Axel’One, 87 avenue des Frères Perret, 69192 Saint-Fons, France
| | - Caroll Vergelati
- Laboratoire des polymères et Matériaux Avancés, UMR 5268 Solvay/CNRS, Solvay in Axel’One, 87 avenue des Frères Perret, 69192 Saint-Fons, France
| | - Paul Sotta
- Laboratoire des polymères et Matériaux Avancés, UMR 5268 Solvay/CNRS, Solvay in Axel’One, 87 avenue des Frères Perret, 69192 Saint-Fons, France
| | - Didier R. Long
- Laboratoire des polymères et Matériaux Avancés, UMR 5268 Solvay/CNRS, Solvay in Axel’One, 87 avenue des Frères Perret, 69192 Saint-Fons, France
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20
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Chang J, Lin Y, Chen W, Tian F, Chen P, Zhao J, Li L. Structural origin for the strain rate dependence of mechanical response of fluoroelastomer F2314. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/polb.24817] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jiarui Chang
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
| | - Yuanfei Lin
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
- South China Advanced Institute for Soft Matter Science and TechnologySouth China University of Technology Guangzhou 510640 China
| | - Wei Chen
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
| | - Fucheng Tian
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
| | - Pinzhang Chen
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
| | - Jingyun Zhao
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
| | - Liangbin Li
- National Synchrotron Radiation Laboratory, CAS Key Laboratory of Soft Matter Chemistry, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of China Hefei 230026 China
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21
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Wang F, Chen S, Wu Q, Zhang R, Sun P. Strain-induced structural and dynamic changes in segmented polyurethane elastomers. POLYMER 2019. [DOI: 10.1016/j.polymer.2018.12.062] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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22
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Bae S, Galant O, Diesendruck CE, Silberstein MN. The Effect of Intrachain Cross-Linking on the Thermomechanical Behavior of Bulk Polymers Assembled Solely from Single Chain Polymer Nanoparticles. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01027] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Suwon Bae
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Or Galant
- Schulich Faculty of Chemistry and Russell-Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa, Israel
| | - Charles E. Diesendruck
- Schulich Faculty of Chemistry and Russell-Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa, Israel
| | - Meredith N. Silberstein
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14850, United States
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23
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Rottler J. Molecular mobility in driven monomeric and polymeric glasses. Phys Rev E 2018; 98:010501. [PMID: 30110863 DOI: 10.1103/physreve.98.010501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Indexed: 11/07/2022]
Abstract
We show that in monomeric supercooled liquids and glasses that are plastically flowing at a constant shear stress σ while being deformed with strain rate ε[over ̇], the microscopic structural relaxation time τ_{str} is given by the universal relation σ/G_{∞}ε[over ̇] with G_{∞} a modulus. This equality holds for all rheological regimes from temperatures above the glass transition all the way to the athermal limit, and arises from the competing effects of elastic loading and viscous dissipation. In macromolecular (polymeric) glasses, however, the stress decouples from this relaxation time and τ_{str} is in fact further reduced even though σ rises during glassy strain hardening. We develop expressions to capture both effects and thus provide a framework for analyzing mobility measurements in glassy materials.
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Affiliation(s)
- Jörg Rottler
- Department of Physics and Astronomy and Quantum Matter Institute, University of British Columbia, Vancouver BC, Canada V6T 1Z1
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24
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Oleinik EF, Mazo MA, Strel’nikov IA, Rudnev SN, Salamatina OB. Plasticity Mechanism for Glassy Polymers: Computer Simulation Picture. POLYMER SCIENCE SERIES A 2018. [DOI: 10.1134/s0965545x18010042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Molinari N, Sutton AP, Mostofi AA. Mechanisms of reinforcement in polymer nanocomposites. Phys Chem Chem Phys 2018; 20:23085-23094. [DOI: 10.1039/c8cp03281e] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Qualitatively different stress–strain responses of polymer nanocomposites are shown to result from the dynamical evolution of three principal molecular structural motifs in the polymer–filler network.
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Affiliation(s)
- N. Molinari
- Department of Physics and the Thomas Young Centre for Theory and Simulation of Materials
- Imperial College London
- London SW7 2AZ
- UK
| | - A. P. Sutton
- Department of Physics and the Thomas Young Centre for Theory and Simulation of Materials
- Imperial College London
- London SW7 2AZ
- UK
| | - A. A. Mostofi
- Department of Physics and the Thomas Young Centre for Theory and Simulation of Materials
- Imperial College London
- London SW7 2AZ
- UK
- Department of Materials and the Thomas Young Centre for Theory and Simulation of Materials
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26
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Shang X, Kröger M, Leimkuhler B. Assessing numerical methods for molecular and particle simulation. SOFT MATTER 2017; 13:8565-8578. [PMID: 29099134 DOI: 10.1039/c7sm01526g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We discuss the design of state-of-the-art numerical methods for molecular dynamics, focusing on the demands of soft matter simulation, where the purposes include sampling and dynamics calculations both in and out of equilibrium. We discuss the characteristics of different algorithms, including their essential conservation properties, the convergence of averages, and the accuracy of numerical discretizations. Formulations of the equations of motion which are suited to both equilibrium and nonequilibrium simulation include Langevin dynamics, dissipative particle dynamics (DPD), and the more recently proposed "pairwise adaptive Langevin" (PAdL) method, which, like DPD but unlike Langevin dynamics, conserves momentum and better matches the relaxation rate of orientational degrees of freedom. PAdL is easy to code and suitable for a variety of problems in nonequilibrium soft matter modeling; our simulations of polymer melts indicate that this method can also provide dramatic improvements in computational efficiency. Moreover we show that PAdL gives excellent control of the relaxation rate to equilibrium. In the nonequilibrium setting, we further demonstrate that while PAdL allows the recovery of accurate shear viscosities at higher shear rates than are possible using the DPD method at identical timestep, it also outperforms Langevin dynamics in terms of stability and accuracy at higher shear rates.
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Affiliation(s)
- Xiaocheng Shang
- Department of Materials, Polymer Physics, ETH Zürich, CH-8093 Zürich, Switzerland.
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27
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Kato K, Nemoto K, Mayumi K, Yokoyama H, Ito K. Ductile Glass of Polyrotaxane Toughened by Stretch-Induced Intramolecular Phase Separation. ACS APPLIED MATERIALS & INTERFACES 2017; 9:32436-32440. [PMID: 28915000 DOI: 10.1021/acsami.7b10845] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A new class of ductile glasses is created from a thermoplastic polyrotaxane. The hard glass, which has a Young's modulus of 1 GPa, shows crazing, necking, and strain hardening with a total elongation of 330%. Stress concentration is prevented through a unique stretch-induced intramolecular phase separation of the cyclic components and the exposed backbone. In situ synchrotron X-ray scattering studies indicate that the backbone polymer chains slip through the cyclic components in the regions where the stress is concentrated.
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Affiliation(s)
- Kazuaki Kato
- Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo , 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
- Research Center for Structural Materials, National Institute for Materials Science , 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Kaito Nemoto
- Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo , 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Koichi Mayumi
- Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo , 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Hideaki Yokoyama
- Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo , 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Kohzo Ito
- Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo , 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
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28
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Parker AJ, Rottler J. Nonlinear Mechanics of Triblock Copolymer Elastomers: From Molecular Simulations to Network Models. ACS Macro Lett 2017. [DOI: 10.1021/acsmacrolett.7b00369] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amanda J. Parker
- Department
of Physics and Astronomy, University of British Columbia, 6224
Agricultural Road, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum
Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Jörg Rottler
- Department
of Physics and Astronomy, University of British Columbia, 6224
Agricultural Road, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum
Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
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29
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Jabbari-Farouji S, Lame O, Perez M, Rottler J, Barrat JL. Role of the Intercrystalline Tie Chains Network in the Mechanical Response of Semicrystalline Polymers. PHYSICAL REVIEW LETTERS 2017; 118:217802. [PMID: 28598647 DOI: 10.1103/physrevlett.118.217802] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Indexed: 06/07/2023]
Abstract
We examine the microscopic origin of the tensile response in semicrystalline polymers by performing large-scale molecular dynamics simulations of various chain lengths. We investigate the microscopic rearrangements of the polymers during tensile deformation and show that the intercrystalline chain connections known as tie chains contribute significantly to the elastic and plastic response. These results suggest that the mechanical behavior of semicrystalline polymers is controlled by two interpenetrated networks of entanglements and tie chains.
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Affiliation(s)
- Sara Jabbari-Farouji
- Institute of Physics, Johannes Gutenberg-University, Staudingerweg 7-9, 55128 Mainz, Germany
| | - Olivier Lame
- Université de Lyon, INSA, MATEIS, UMR CNRS 5510, F69621 Villeurbanne, France
| | - Michel Perez
- Université de Lyon, INSA, MATEIS, UMR CNRS 5510, F69621 Villeurbanne, France
| | - Joerg Rottler
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia V6T 1Z1, Canada
| | - Jean-Louis Barrat
- Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France and CNRS, LIPHY, F-38000 Grenoble, France
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30
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Lin P, Xu Q, Cheng S, Li X, Zhao Z, Sun S, Peng C, Joy A, Wang SQ. Effects of Molecular Weight Reduction on Brittle–Ductile Transition and Elastic Yielding Due to Noninvasive γ Irradiation on Polymer Glasses. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Panpan Lin
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
| | - Quan Xu
- State
Key Laboratory of Heavy Oil Processing, Institute of New Energy Beijing Key Laboratory of Biogas Upgrading Utilization, China University of Petroleum (Beijing), Beijing 102249, China
| | - Shiwang Cheng
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Xiaoxiao Li
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
| | - Zhichen Zhao
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
| | - Shuangyi Sun
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
| | - Chao Peng
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
| | - Abraham Joy
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
| | - Shi-Qing Wang
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
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31
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Yang F, Carpick RW, Srolovitz DJ. Mechanisms of Contact, Adhesion, and Failure of Metallic Nanoasperities in the Presence of Adsorbates: Toward Conductive Contact Design. ACS NANO 2017; 11:490-500. [PMID: 27983792 DOI: 10.1021/acsnano.6b06473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The properties of contacting interfaces are strongly affected not only by the bulk and surface properties of contacting materials but also by the ubiquitous presence of adsorbed contaminants. Here, we focus on the properties of single asperity contacts in the presence of adsorbates within a molecular dynamics description of metallic asperity normal contact and a parametric description of adsorbate properties. A platinum-platinum asperity contact is modeled with adsorbed oligomers with variable properties. This system is particularly tailored to the context of nanoelectromechanical system (NEMS) contact switches, but the results are generally relevant to metal-metal asperity contacts in nonpristine conditions. Even though mechanical forces can displace adsorbate out of the contact region, increasing the adsorbate layer thickness and/or adsorbate/metal adhesion makes it more difficult for metal asperity/metal surface contact to occur, thereby lowering the electrical contact conductance. Contact separation is a competition between plastic necking in the asperity or decohesion at the asperity/substrate interface. The mechanism which operates at a lower tensile stress dominates. Necking dominates when the adsorbate/metal adhesion is strong and/or the adsorbate layer thickness is small. In broad terms, necking implies larger asperity deformation and mechanical work, as compared with decohesion. Optimal NEMS switch performance requires substantial contact conductance and minimal asperity deformation; these results indicate that these goals can be achieved by balancing the quantity of adsorbates and their adhesion to the metal surface.
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Affiliation(s)
- Fan Yang
- Department of Materials Science and Engineering and ‡Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104 United States
| | - Robert W Carpick
- Department of Materials Science and Engineering and ‡Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104 United States
| | - David J Srolovitz
- Department of Materials Science and Engineering and ‡Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104 United States
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32
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Ge T, Tzoumanekas C, Anogiannakis SD, Hoy RS, Robbins MO. Entanglements in Glassy Polymer Crazing: Cross-Links or Tubes? Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b02125] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ting Ge
- Department
of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Christos Tzoumanekas
- Department
of Materials Science and Engineering, School of Chemical Engineering, National Technical University of Athens, Athens 15780, Greece
| | - Stefanos D. Anogiannakis
- Department
of Materials Science and Engineering, School of Chemical Engineering, National Technical University of Athens, Athens 15780, Greece
| | - Robert S. Hoy
- Department
of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Mark O. Robbins
- Department
of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
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33
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Kolluru PV, Chasiotis I. A master curve for the size and strain rate dependent large deformation behavior of PS nanofibers at room temperature. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.07.046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Rottler J. Relaxation times in deformed polymer glasses: A comparison between molecular simulations and two theories. J Chem Phys 2016. [DOI: 10.1063/1.4960208] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jörg Rottler
- Departments of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia V6T 1Z1, Canada
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35
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Nazarychev VM, Lyulin AV, Larin SV, Gurtovenko AA, Kenny JM, Lyulin SV. Molecular dynamics simulations of uniaxial deformation of thermoplastic polyimides. SOFT MATTER 2016; 12:3972-3981. [PMID: 27033967 DOI: 10.1039/c6sm00230g] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The results of atomistic molecular-dynamics simulations of mechanical properties of heterocyclic polymer subjected to uniaxial deformation are reported. A new amorphous thermoplastic polyimide R-BAPO with a repeat unit consisting of dianhydride 1,3-bis-(3',4,-dicarboxyphenoxy)diphenyl (dianhydride R) and diamine 4,4'-bis-(4''-aminophenoxy)diphenyloxide (diamine BAPO) was chosen for the simulations. Our primary goal was to establish the impact of various factors (sample preparation method, molecular mass, and cooling and deformation rates) on the elasticity modulus. In particular, we found that the elasticity modulus was only slightly affected by the degree of equilibration, the molecular mass and the size of the simulation box. This is most likely due to the fact that the main contribution to the elasticity modulus is from processes on scales smaller than the entanglement length. Essentially, our simulations reproduce the logarithmic dependence of the elasticity modulus on cooling and deformation rates, which is normally observed in experiments. With the use of the temperature dependence analysis of the elasticity modulus we determined the flow temperature of R-BAPO to be 580 K in line with the experimental data available. Furthermore, we found that the application of high external pressure to the polymer sample during uniaxial deformation can improve the mechanical properties of the polyimide. Overall, the results of our simulations clearly demonstrate that atomistic molecular-dynamics simulations represent a powerful and accurate tool for studying the mechanical properties of heterocyclic polymers and can therefore be useful for the virtual design of new materials, thereby supporting cost-effective synthesis and experimental research.
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Affiliation(s)
- V M Nazarychev
- Institute of Macromolecular Compounds, Russian Academy of Sciences, Bol'shoi pr. 31 (V.O.), St. Petersburg, 199004, Russia.
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36
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Lin P, Liu J, Wang SQ. Delineating nature of stress responses during ductile uniaxial extension of polycarbonate glass. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.02.051] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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37
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Zhao J, Yu P, Dong S. The Influence of Crosslink Density on the Failure Behavior in Amorphous Polymers by Molecular Dynamics Simulations. MATERIALS (BASEL, SWITZERLAND) 2016; 9:E234. [PMID: 28773360 PMCID: PMC5502881 DOI: 10.3390/ma9040234] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 03/04/2016] [Accepted: 03/17/2016] [Indexed: 11/25/2022]
Abstract
The crosslink density plays a key role in the mechanical response of the amorphous polymers in previous experiments. However, the mechanism of the influence is still not clear. In this paper, the influence of crosslink density on the failure behavior under tension and shear in amorphous polymers is systematically studied using molecular dynamics simulations. The present results indicate that the ultimate stresses and the broken ratios (the broken bond number to all polymer chain number ratios) increase, as well as the ultimate strains decrease with increasing crosslink density. The strain concentration is clearer with the increase of crosslink density. In other words, a higher crosslink density leads to a higher strain concentration. Hence, the higher strain concentration further reduces the fracture strain. This study implies that the mechanical properties of amorphous polymers can be dominated for different applications by altering the molecular architecture.
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Affiliation(s)
- Junhua Zhao
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, Jiangnan University, Wuxi 214122, China.
| | - Peishi Yu
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, Jiangnan University, Wuxi 214122, China.
| | - Shuhong Dong
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, Jiangnan University, Wuxi 214122, China.
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38
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Wang L, Liu H, Li F, Shen J, Zheng Z, Gao Y, Liu J, Wu Y, Zhang L. Stress–strain behavior of block-copolymers and their nanocomposites filled with uniform or Janus nanoparticles under shear: a molecular dynamics simulation. Phys Chem Chem Phys 2016; 18:27232-27244. [DOI: 10.1039/c6cp05853a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We adopted molecular dynamics simulation to study the relation between the ordered structures and the resulting mechanical properties of block copolymers filled with uniform or Janus nanoparticles.
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Affiliation(s)
- Lu Wang
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
| | - Hongji Liu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
| | - Fanzhu Li
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
| | - Jianxiang Shen
- College of Materials and Textile Engineering
- Jiaxing University
- Jiaxing 314001
- P. R. China
| | - Zijian Zheng
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
- Engineering Research Center of Elastomer Materials on Energy Conservation and Resources
| | - Yangyang Gao
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
- Engineering Research Center of Elastomer Materials on Energy Conservation and Resources
| | - Jun Liu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
- Engineering Research Center of Elastomer Materials on Energy Conservation and Resources
| | - Youping Wu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
- Engineering Research Center of Elastomer Materials on Energy Conservation and Resources
| | - Liqun Zhang
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
- People's Republic of China
- Beijing Engineering Research Center of Advanced Elastomers
- People's Republic of China
- Engineering Research Center of Elastomer Materials on Energy Conservation and Resources
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39
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Liu J, Lin P, Cheng S, Wang W, Mays JW, Wang SQ. Polystyrene Glasses under Compression: Ductile and Brittle Responses. ACS Macro Lett 2015; 4:1072-1076. [PMID: 35614806 DOI: 10.1021/acsmacrolett.5b00442] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polystyrene of different molecular weights and their binary mixtures are studied in terms of their various mechanical responses to uniaxial compression at different temperatures. PS of Mw = 25 kg/mol is completely brittle until it is above its glass transition temperature Tg. In contrast, upon incorporation of a high molecular weight component, PS mixtures turn from barely ductile a few degrees below its Tg to ductile over 40° below Tg. In the upper limit, a PS of Mw = 319 kg/mol yields and undergoes plastic flow, even at T = -70 °C. The observed dependence of mechanical responses on molecular weight and molecular weight distribution can be adequately rationalized by the idea that yielding and plastic compression are caused by chain networking.
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Affiliation(s)
- Jianning Liu
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325, United States
| | - Panpan Lin
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325, United States
| | - Shiwang Cheng
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Weiyu Wang
- Department
of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Jimmy W. Mays
- Department
of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Shi-Qing Wang
- Department
of Polymer Science, University of Akron, Akron, Ohio 44325, United States
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40
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Gendelman O, Hentschel HGE, Mishra PK, Procaccia I, Zylberg J. Elasticity and plasticity in stiff and flexible oligomeric glasses. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:042315. [PMID: 25375502 DOI: 10.1103/physreve.90.042315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Indexed: 06/04/2023]
Abstract
In this paper we focus on the mechanical properties of oligomeric glasses (waxes), employing a microscopic model that provides, via numerical simulations, information about the shear modulus of such materials, the failure mechanism via plastic instabilities, and the geometric responses of the oligomers themselves to a mechanical load. We present a microscopic theory that explains the numerically observed phenomena, including an exact theory of the shear modulus and of the plastic instabilities, both local and system spanning. In addition we present a model to explain the geometric changes in the oligomeric chains under increasing strains.
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Affiliation(s)
- Oleg Gendelman
- Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | | | - Pankaj K Mishra
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Itamar Procaccia
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jacques Zylberg
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
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41
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Ge T, Grest GS, Robbins MO. Tensile Fracture of Welded Polymer Interfaces: Miscibility, Entanglements, and Crazing. Macromolecules 2014. [DOI: 10.1021/ma501473q] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ting Ge
- Department
of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
- Department
of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, United States
| | - Gary S. Grest
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Mark O. Robbins
- Department
of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
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42
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Tang S, Li Y, Liu WK, Huang XX. Surface Ripples of Polymeric Nanofibers under Tension: The Crucial Role of Poisson’s Ratio. Macromolecules 2014. [DOI: 10.1021/ma5012599] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shan Tang
- Department
of Engineering Mechanics, Chongqing University, Chongqing, China, 400017
| | - Ying Li
- Department
of Mechanical Engineering, Northwestern University, Evanston, Illinois, United States
| | - Wing Kam Liu
- Department
of Mechanical Engineering, Northwestern University, Evanston, Illinois, United States
- Distinguished
Scientists Program Committee, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Xiao Xu Huang
- College
of Material Science and Engineering, Chongqing University, Chongqing, China, 400017
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43
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Wang SQ, Cheng S, Lin P, Li X. A phenomenological molecular model for yielding and brittle-ductile transition of polymer glasses. J Chem Phys 2014; 141:094905. [DOI: 10.1063/1.4893765] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Shi-Qing Wang
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325, USA
| | - Shiwang Cheng
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325, USA
| | - Panpan Lin
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325, USA
| | - Xiaoxiao Li
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325, USA
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44
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Lin P, Cheng S, Wang SQ. Strain Hardening During Uniaxial Compression of Polymer Glasses. ACS Macro Lett 2014; 3:784-787. [PMID: 35590699 DOI: 10.1021/mz5004129] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The origin of high mechanical stresses in large deformation of polymer glasses has been elusive because both plasticity and elasticity take place. In this work on the nature of the mechanical responses, we carry out uniaxial compression experiments to make simultaneous mechanical and thermal measurements of polycarbonate. Our results confirm that two factors contribute to the growing mechanical stress in the post-yield regime, which is known as "strain hardening". Besides plastic deformation that is intersegmental in origin, chain tension as an intrasegmental component contributes considerably to the measured stress in post-yield. Such a conclusion modifies the previous consensus regarding the nature of strain hardening in mechanical deformation of polymer glasses.
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Affiliation(s)
- Panpan Lin
- Maurice
Morton Institute
of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Shiwang Cheng
- Maurice
Morton Institute
of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Shi-Qing Wang
- Maurice
Morton Institute
of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
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Sun H, Liu G, Ntetsikas K, Avgeropoulos A, Wang SQ. Rheology of Entangled Polymers Not Far above Glass Transition Temperature: Transient Elasticity and Intersegmental Viscous Stress. Macromolecules 2014. [DOI: 10.1021/ma500899s] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Hao Sun
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Gengxin Liu
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Konstantinos Ntetsikas
- Department of Materials Science and Engineering, University of Ioannina, University Campus, Ioannina, 45110, Greece
| | - Apostolos Avgeropoulos
- Department of Materials Science and Engineering, University of Ioannina, University Campus, Ioannina, 45110, Greece
| | - Shi-Qing Wang
- Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
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Yang S, Qu J. Coarse-grained molecular dynamics simulations of the tensile behavior of a thermosetting polymer. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:012601. [PMID: 25122326 DOI: 10.1103/physreve.90.012601] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Indexed: 06/03/2023]
Abstract
Using a previously developed coarse-grained model, we conducted large-scale (∼ 85 × 85 × 85 nm(3)) molecular dynamics simulations of uniaxial-strain deformation to study the tensile behavior of an epoxy molding compound, epoxy phenol novolacs (EPN) bisphenol A (BPA). Under the uniaxial-strain deformation, the material is found to exhibit cavity nucleation and growth, followed by stretching of the ligaments separated by the cavities, until the ultimate failure through ligament scissions. The nucleation sites of cavities are rather random and the subsequent cavity growth accounts for much (87%) of the volumetric change during the uniaxial-strain deformation. Ultimate failure of the materials occurs when the cavity volume fraction reaches ∼ 60%. During the entire deformation process, polymer strands in the network are continuously extended to their linear states and broken in the postyielding strain hardening stage. When most of the strands are stretched to their taut configurations, rapid scission of a large number of strands occurs within a small strain increment, which eventually leads to fracture. Finally, through extensive numerical simulations of various loading conditions in addition to uniaxial strain, we find that yielding of the EPN-BPA can be described by the pressure-modified von Mises yield criterion.
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Affiliation(s)
- Shaorui Yang
- Department Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, USA
| | - Jianmin Qu
- Department Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, USA and Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois 60208, USA
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Ge T, Robbins MO, Perahia D, Grest GS. Healing of polymer interfaces: Interfacial dynamics, entanglements, and strength. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:012602. [PMID: 25122327 DOI: 10.1103/physreve.90.012602] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Indexed: 05/23/2023]
Abstract
Self-healing of polymer films often takes place as the molecules diffuse across a damaged region, above their melting temperature. Using molecular dynamics simulations we probe the healing of polymer films and compare the results with those obtained for thermal welding of homopolymer slabs. These two processes differ from each other in their interfacial structure since damage leads to increased polydispersity and more short chains. A polymer sample was cut into two separate films that were then held together in the melt state. The recovery of the damaged film was followed as time elapsed and polymer molecules diffused across the interface. The mass uptake and formation of entanglements, as obtained from primitive path analysis, are extracted and correlated with the interfacial strength obtained from shear simulations. We find that the diffusion across the interface is significantly faster in the damaged film compared to welding because of the presence of short chains. Though interfacial entanglements increase more rapidly for the damaged films, a large fraction of these entanglements are near chain ends. As a result, the interfacial strength of the healing film increases more slowly than for welding. For both healing and welding, the interfacial strength saturates as the bulk entanglement density is recovered across the interface. However, the saturation strength of the damaged film is below the bulk strength for the polymer sample. At saturation, cut chains remain near the healing interface. They are less entangled and as a result they mechanically weaken the interface. Chain stiffness increases the density of entanglements, which increases the strength of the interface. Our results show that a few entanglements across the interface are sufficient to resist interfacial chain pullout and enhance the mechanical strength.
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Affiliation(s)
- Ting Ge
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Mark O Robbins
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Dvora Perahia
- Department of Chemistry, Clemson University, Clemson, South Carolina 29634, USA
| | - Gary S Grest
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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Affiliation(s)
- Shiwang Cheng
- Maurice Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Shi-Qing Wang
- Maurice Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
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Ge T, Grest GS, Robbins MO. Structure and Strength at Immiscible Polymer Interfaces. ACS Macro Lett 2013; 2:882-886. [PMID: 35607008 DOI: 10.1021/mz400407m] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thermal welding of polymer-polymer interfaces is important for integrating polymeric elements into devices. When two different polymers are joined, the strength of the weld depends critically on the degree of immiscibility. We perform large-scale molecular dynamics simulations of the structure-strength relation at immiscible polymer interfaces. Our simulations show that immiscibility arrests interdiffusion and limits the equilibrium interfacial width. Even for weakly immiscible films, the narrow interface is unable to transfer stress upon deformation as effectively as the bulk material, and chain pullout at the interface becomes the dominant failure mechanism. This greatly reduces the interfacial strength. The weak response of immiscible interfaces is shown to arise from an insufficient density of entanglements across the interface. We demonstrate that there is a threshold interfacial width below which no significant entanglements can form between opposite sides to strengthen the interface.
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Affiliation(s)
- Ting Ge
- Department
of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gary S. Grest
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Mark O. Robbins
- Department
of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, United States
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Chao H, Riggleman RA. Effect of particle size and grafting density on the mechanical properties of polymer nanocomposites. POLYMER 2013. [DOI: 10.1016/j.polymer.2013.07.018] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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