1
|
Dietz JD, Nan K, Hoy RS. Unexpected Ductility in Semiflexible Polymer Glasses with Entanglement Length Equal to Their Kuhn Length. PHYSICAL REVIEW LETTERS 2022; 129:127801. [PMID: 36179170 DOI: 10.1103/physrevlett.129.127801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 08/29/2022] [Indexed: 06/16/2023]
Abstract
Semiflexible polymer glasses (SPGs), including those formed by the recently synthesized semiflexible conjugated polymers, are expected to be brittle because classical formulas for their craze extension ratio λ_{craze} and fracture stretch λ_{frac} predict that systems with N_{e}=C_{∞} have λ_{craze}=λ_{frac}=1 and hence cannot be deformed to large strains. Using molecular dynamics simulations, we show that in fact such glasses can form stable crazes with λ_{craze}≃N_{e}^{1/4}≃C_{∞}^{1/4}, and that they fracture at λ_{frac}=(3N_{e}^{1/2}-2)^{1/2}≃(3C_{∞}^{1/2}-2)^{1/2}. We argue that the classical formulas for λ_{craze} and λ_{frac} fail to describe SPGs' mechanical response because they do not account for Kuhn segments' ability to stretch during deformation.
Collapse
Affiliation(s)
- Joseph D Dietz
- Department of Physics, University of South Florida, Tampa, Florida 33620-7100, USA
| | - Kai Nan
- Department of Physics, University of South Florida, Tampa, Florida 33620-7100, USA
| | - Robert S Hoy
- Department of Physics, University of South Florida, Tampa, Florida 33620-7100, USA
| |
Collapse
|
2
|
Wang J, in ’t Veld PJ, Robbins MO, Ge T. Effects of Coarse-Graining on Molecular Simulation of Craze Formation in Polymer Glass. Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c01969] [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)
- 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
| | - Ting Ge
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| |
Collapse
|
3
|
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
| |
Collapse
|
4
|
David A, Tartaglino U, Casalegno M, Raos G. Fracture in Silica/Butadiene Rubber: A Molecular Dynamics View of Design-Property Relationships. ACS POLYMERS AU 2021; 1:175-186. [PMID: 36855656 PMCID: PMC9954208 DOI: 10.1021/acspolymersau.1c00023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Despite intense investigation, the mechanisms governing the mechanical reinforcement of polymers by dispersed nanoparticles have only been partially clarified. This is especially true for the ultimate properties of the nanocomposites, which depend on their resistance to fracture at large deformations. In this work, we adopt molecular dynamics simulations to investigate the mechanical properties of silica/polybutadiene rubber, using a quasi-atomistic model that allows a meaningful description of bond breaking and fracture over relatively large length scales. The behavior of large nanocomposite models is explored systematically by tuning the cross-linking, grafting densities, and nanoparticle concentration. The simulated stress-strain curves are interpreted by monitoring the breaking of chemical bonds and the formation of voids, up to complete rupture of the systems. We find that some chemical bonds, and particularly the S-S linkages at the rubber-nanoparticle interface, start breaking well before the appearance of macroscopic features of fracture and yield.
Collapse
Affiliation(s)
- Alessio David
- Department
of Chemistry, Materials and Chemical Engineering, “G. Natta”, Politecnico di Milano, Milano 20131, Italy
| | | | - Mosè Casalegno
- Department
of Chemistry, Materials and Chemical Engineering, “G. Natta”, Politecnico di Milano, Milano 20131, Italy
| | - Guido Raos
- Department
of Chemistry, Materials and Chemical Engineering, “G. Natta”, Politecnico di Milano, Milano 20131, Italy,Email for G.R.:
| |
Collapse
|
5
|
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
| |
Collapse
|
6
|
Affiliation(s)
- Jiuling Wang
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Ting Ge
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| |
Collapse
|
7
|
Tang Z, Fujimoto K, Okazaki S. A comparison of the brittle PMMA with the ductile PC on the elasticity and yielding from a molecular dynamics perspective. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
8
|
Kinjo T, Yoneyama H, Umemoto K. Molecular Dynamics Simulation of Fracture at a Polymer and Metal Oxide Joining Interface. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Tomoyuki Kinjo
- Toyota Central R&D Labs., Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192
| | - Hiroaki Yoneyama
- Toyota Central R&D Labs., Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192
| | - Kazuhiko Umemoto
- Toyota Central R&D Labs., Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192
| |
Collapse
|
9
|
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
| |
Collapse
|
10
|
Affiliation(s)
- Qing Peng
- Physics Department King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia
- Researcher at K.A.CARE Energy Research & Innovation Center at Dhahran Dhahran 31261 Saudi Arabia
| | - Binghui Deng
- Manufacturing Technology and Engineering Corning Incorporated Corning NY 14831 USA
| | - Marcel Utz
- School of Chemistry University of Southampton Southampton SO17 1BJ U.K
| |
Collapse
|
11
|
Tang Z, Fujimoto K, Okazaki S. All-atom molecular dynamics study of impact fracture of glassy polymers. II: Microscopic origins of stresses in elasticity, yielding, and strain hardening. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122908] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
12
|
Li H, Wu H, Li B, Gao Y, Zhao X, Zhang L. Molecular dynamics simulation of fracture mechanism in the double interpenetrated cross-linked polymer. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122571] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
13
|
Ethier JG, Drummy LF, Vaia RA, Hall LM. Uniaxial Deformation and Crazing in Glassy Polymer-Grafted Nanoparticle Ultrathin Films. ACS NANO 2019; 13:12816-12829. [PMID: 31609111 DOI: 10.1021/acsnano.9b05001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The deformation behavior of neat, glassy polymer-grafted nanoparticle (PGN) monolayer films is studied using coarse-grained molecular dynamics simulations and experiments on polystyrene-grafted silica. In both the simulations and experiments, apparent crazing behavior is observed during deformation. The PGN systems show a relatively more uniform, perforated sheet craze structure and significantly higher strain at break than reference homopolymers of the same length. Short chain, unentangled PGN monolayers are also simulated for comparison; these are brittle and break apart without crazing. The entangled PGN simulations are analyzed in detail for systems at both high and moderate graft density. Stress-strain curves show three distinct regions: yielding and strain localization, craze widening, and strain hardening preceding catastrophic failure. The PGN stress-strain behavior appears more similar to that of longer chain, highly entangled homopolymer films than to the reference homopolymer films of the same length as the graft chains, suggesting that the particles effectively add additional entanglement points. The moderate graft density particles have higher strain-to-failure and maximum stress than the high graft density particles. We suggest this increased robustness for lower graft density systems is due to their increased interpenetration of graft chains between neighboring particles, which leads to increased interparticle entanglements per chain.
Collapse
Affiliation(s)
- Jeffrey G Ethier
- William G. Lowrie Department of Chemical and Biomolecular Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Lawrence F Drummy
- Materials and Manufacturing Directorate , Air Force Research Laboratories , WPAFB , Ohio 45433 , United States
| | - Richard A Vaia
- Materials and Manufacturing Directorate , Air Force Research Laboratories , WPAFB , Ohio 45433 , United States
| | - Lisa M Hall
- William G. Lowrie Department of Chemical and Biomolecular Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
| |
Collapse
|
14
|
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]
|
15
|
Higuchi Y. Stress Transmitters at the Molecular Level in the Deformation and Fracture Processes of the Lamellar Structure of Polyethylene via Coarse-Grained Molecular Dynamics Simulations. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00636] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuji Higuchi
- Institute for Solid State Physics, The University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba 277-8581, Japan
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira,
Aoba-ku, Sendai, Miyagi 980-8577, Japan
| |
Collapse
|
16
|
Chan EP, Xie W, Orski SV, Lee JH, Soles CL. Entanglement Density-Dependent Energy Absorption of Polycarbonate Films via Supersonic Fracture. ACS Macro Lett 2019; 8:806-811. [PMID: 35619502 PMCID: PMC10941953 DOI: 10.1021/acsmacrolett.9b00264] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The fracture behavior of glassy polymers is strongly coupled to molecular parameters such as entanglement density as well as extrinsic parameters such as strain rate and test temperature. Here we use laser-induced projectile impact testing (LIPIT) to study the extreme strain rate (≈107 s-1) puncture behavior of free-standing polycarbonate (PC) thin films. We demonstrate that changes to the PC molecular mass and the degree of plasticization can lead to substantial changes in the specific puncture energy. We relate these changes to the alteration of the entanglement density of the polymer that determines the underlying failure mechanism as well as the size of the deformation zone.
Collapse
Affiliation(s)
- Edwin P. Chan
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Wanting Xie
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Department of Mechanical and Industrial Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Sara V. Orski
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Jae-Hwang Lee
- Department of Mechanical and Industrial Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Christopher L. Soles
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| |
Collapse
|
17
|
Nguyen HT, Hoy RS. Effect of the Ratio lK/p on Glassy-Polymeric Shear Deformation Mechanisms. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00651] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hong T. Nguyen
- 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
| |
Collapse
|
18
|
Higuchi Y. Fracture processes of crystalline polymers using coarse-grained molecular dynamics simulations. Polym J 2018. [DOI: 10.1038/s41428-018-0067-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
19
|
Higuchi Y, Saito K, Sakai T, Gong JP, Kubo M. Fracture Process of Double-Network Gels by Coarse-Grained Molecular Dynamics Simulation. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00124] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Yuji Higuchi
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
- PRESTO, Japan Science and Technology Agency (JST),
4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba 277-8581, Japan
| | - Keisuke Saito
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Takamasa Sakai
- PRESTO, Japan Science and Technology Agency (JST),
4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Jian Ping Gong
- Faculty of Advanced Life Science and Soft Matter GI-CoRE, Hokkaido University, N21W11, Kita-ku, Sapporo 001-0021, Japan
| | - Momoji Kubo
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| |
Collapse
|
20
|
Morthomas J, Fusco C, Zhai Z, Lame O, Perez M. Crystallization of finite-extensible nonlinear elastic Lennard-Jones coarse-grained polymers. Phys Rev E 2017; 96:052502. [PMID: 29347659 DOI: 10.1103/physreve.96.052502] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Indexed: 06/07/2023]
Abstract
The ability of a simple coarse-grained finite-extensible nonlinear elastic (FENE) Lennard-Jones (LJ) polymer model to be crystallized is investigated by molecular dynamics simulations. The optimal FENE Lennard-Jones parameter combinations (ratio between FENE and LJ equilibrium distances) and the optimal lattice parameters are calculated for five different perfect crystallite structures: simple tetragonal, body-centered tetragonal, body-centered orthorhombic, hexagonal primitive, and hexagonal close packed. It was found that the most energetically favorable structure is the body-centered orthorhombic. Starting with an equilibrated polymer liquid and with the optimal parameters found for the body-centered orthorhombic, an isothermal treatment led to the formation of large lamellar crystallites with a typical chain topology: folded, loop, and tie chains, and with a crystallinity of about 60%-70%, similar to real semicrystalline polymers. This simple coarse-grained Lennard-Jones model provides a qualitative tool to study semicrystalline microstructures for polymers.
Collapse
Affiliation(s)
- Julien Morthomas
- INSA de Lyon, Université de Lyon, MATEIS, UMR CNRS 5510, 69621 Villeurbanne, France
| | - Claudio Fusco
- INSA de Lyon, Université de Lyon, MATEIS, UMR CNRS 5510, 69621 Villeurbanne, France
| | - Zengqiang Zhai
- INSA de Lyon, Université de Lyon, MATEIS, UMR CNRS 5510, 69621 Villeurbanne, France
| | - Olivier Lame
- INSA de Lyon, Université de Lyon, MATEIS, UMR CNRS 5510, 69621 Villeurbanne, France
| | - Michel Perez
- INSA de Lyon, Université de Lyon, MATEIS, UMR CNRS 5510, 69621 Villeurbanne, France
| |
Collapse
|
21
|
Higuchi Y, Kubo M. Deformation and Fracture Processes of a Lamellar Structure in Polyethylene at the Molecular Level by a Coarse-Grained Molecular Dynamics Simulation. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02613] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yuji Higuchi
- Institute
for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
- PRESTO, Japan
Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Momoji Kubo
- Institute
for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| |
Collapse
|
22
|
Zhao Y, Liu J, Li X, Lu Y, Wang SQ. How and Why Polymer Glasses Lose Their Ductility Due to Plasticizers. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02158] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yue Zhao
- Department of Polymer Science
and Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Jianning Liu
- Department of Polymer Science
and Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Xiaoxiao Li
- Department of Polymer Science
and Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Yue Lu
- Department of Polymer Science
and Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| | - Shi-Qing Wang
- Department of Polymer Science
and Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325-3909, United States
| |
Collapse
|
23
|
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]
|
24
|
Dong H, Sliozberg YR, Snyder JF, Steele J, Chantawansri TL, Orlicki JA, Walck SD, Reiner RS, Rudie AW. Highly Transparent and Toughened Poly(methyl methacrylate) Nanocomposite Films Containing Networks of Cellulose Nanofibrils. ACS APPLIED MATERIALS & INTERFACES 2015; 7:25464-25472. [PMID: 26513136 DOI: 10.1021/acsami.5b08317] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cellulose nanofibrils (CNFs) are a class of cellulosic nanomaterials with high aspect ratios that can be extracted from various natural sources. Their highly crystalline structures provide the nanofibrils with excellent mechanical and thermal properties. The main challenges of CNFs in nanocomposite applications are associated with their high hydrophilicity, which makes CNFs incompatible with hydrophobic polymers. In this study, highly transparent and toughened poly(methyl methacrylate) (PMMA) nanocomposite films were prepared using various percentages of CNFs covered with surface carboxylic acid groups (CNF-COOH). The surface groups make the CNFs interfacial interaction with PMMA favorable, which facilitate the homogeneous dispersion of the hydrophilic nanofibrils in the hydrophobic polymer and the formation of a percolated network of nanofibrils. The controlled dispersion results in high transparency of the nanocomposites. Mechanical analysis of the resulting films demonstrated that a low percentage loading of CNF-COOH worked as effective reinforcing agents, yielding more ductile and therefore tougher films than the neat PMMA film. Toughening mechanisms were investigated through coarse-grained simulations, where the results demonstrated that a favorable polymer-nanofibril interface together with percolation of the nanofibrils, both facilitated through hydrogen bonding interactions, contributed to the toughness improvement in these nanocomposites.
Collapse
Affiliation(s)
- Hong Dong
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
- TKC Global Solutions, LLC , Aberdeen, Maryland 21005, United States
| | - Yelena R Sliozberg
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
- TKC Global Solutions, LLC , Aberdeen, Maryland 21005, United States
| | - James F Snyder
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
| | - Joshua Steele
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
| | - Tanya L Chantawansri
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
| | - Joshua A Orlicki
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
| | - Scott D Walck
- Macromolecular Science & Technology Branch, U.S. Army Research Laboratory , Aberdeen Proving Ground, Maryland 21005, United States
- TKC Global Solutions, LLC , Aberdeen, Maryland 21005, United States
| | - Richard S Reiner
- Forest Products Laboratory, USDA Forest Service , Madison, Wisconsin 53726, United States
| | - Alan W Rudie
- Forest Products Laboratory, USDA Forest Service , Madison, Wisconsin 53726, United States
| |
Collapse
|
25
|
Hoyle DM, Fielding SM. Age-dependent modes of extensional necking instability in soft glassy materials. PHYSICAL REVIEW LETTERS 2015; 114:158301. [PMID: 25933343 DOI: 10.1103/physrevlett.114.158301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Indexed: 06/04/2023]
Abstract
We study the instability to necking of an initially cylindrical filament of soft glassy material subject to extensional stretching. By numerical simulation of the soft glassy rheology model and a simplified fluidity model, and by analytical predictions within a highly generic toy description, we show that the mode of instability is set by the age of the sample relative to the inverse of the applied extensional strain rate. Young samples neck gradually via a liquidlike mode, the onset of which is determined by both the elastic loading and plastic relaxation terms in the stress constitutive equation. Older samples fail at smaller draw ratios via a more rapid mode, the onset of which is determined only by the solidlike elastic loading terms (though plastic effects arise later, once appreciable necking develops). We show this solidlike mode to be the counterpart, for elastoplastic materials, of the Considère mode of necking in strain-rate-independent solids.
Collapse
Affiliation(s)
- David M Hoyle
- Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom
| | - Suzanne M Fielding
- Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom
| |
Collapse
|
26
|
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.
Collapse
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
| |
Collapse
|
27
|
Torres JP, Frontini PM, Aretxabaleta L. Experimental characterization and computational simulations of the low-velocity impact behaviour of polypropylene. POLYM INT 2013. [DOI: 10.1002/pi.4563] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Juan P Torres
- Instituto Nacional de Tecnología y Ciencia de Materiales INTEMA; Universidad Nacional de Mar del Plata; CONICET, Av. J. B. Justo 4302 B7608FDQ Mar del Plata Argentina
| | - Patricia M Frontini
- Instituto Nacional de Tecnología y Ciencia de Materiales INTEMA; Universidad Nacional de Mar del Plata; CONICET, Av. J. B. Justo 4302 B7608FDQ Mar del Plata Argentina
| | - Laurentzi Aretxabaleta
- Department of Mechanical Engineering, Mondragon Goi Skola Politeknikoa; Mondragon Uniberstsitatea; Loramend 4 20500 Mondragon Spain
| |
Collapse
|
28
|
Cheng S, Wang SQ. Elastic yielding in cold drawn polymer glasses well below the glass transition temperature. PHYSICAL REVIEW LETTERS 2013; 110:065506. [PMID: 23432274 DOI: 10.1103/physrevlett.110.065506] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 11/30/2012] [Indexed: 06/01/2023]
Abstract
This Letter reports elastic-driven internal yielding in strained ductile polymer glasses. After cold drawing of two different polymer glasses to neck at room temperature, we show that the samples display considerable retractive stress when warmed up above the storage temperature but still considerably below their glass transition temperatures. We conclude that the elastic yielding arises from the distortion of backbones leading to intra-segmental tension in the chain network.
Collapse
Affiliation(s)
- Shiwang Cheng
- Maurice Morton Institute of Polymer Science and Engineering, University of Akron, Akron, Ohio 44325, USA
| | | |
Collapse
|
29
|
|
30
|
|
31
|
Tang Q, Hu W. Molecular simulation of structural relaxation in ultrathin polymer films. Phys Chem Chem Phys 2013; 15:20679-90. [DOI: 10.1039/c3cp53555j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
32
|
McGraw JD, Fowler PD, Ferrari ML, Dalnoki-Veress K. Relaxation of non-equilibrium entanglement networks in thin polymer films. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:7. [PMID: 23355094 DOI: 10.1140/epje/i2013-13007-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 01/11/2013] [Indexed: 06/01/2023]
Abstract
It is known that polymer films, prepared by spin coating, inherit non-equilibrium configurations which can affect macroscopic film properties. Here we present the results of crazing experiments that support this claim; our measurements indicate that the as-cast chain configurations are strongly stretched as compared to equilibrium Gaussian configurations. The results of our experiments also demonstrate that the entanglement network equilibrates on a time scale comparable to one reptation time. Having established that films can be prepared with an equilibrium entanglement network, we proceed by confining polymers to films in which the thickness is comparable to the molecular size. By stacking two such films, a bilayer is created with a buried entropic interface. Such an interface has no enthalpic cost, only an entropic penalty associated with the restricted configurations of molecules that cannot cross the mid-plane of the bilayer. In the melt, the entropic interface heals as chains from the two layers mix and entangle with one another; crazing measurements allow us to probe the dynamics of two films becoming one. Healing of the entropic interface is found to take less than one bulk reptation time.
Collapse
Affiliation(s)
- Joshua D McGraw
- Department of Physics & Astronomy and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada
| | | | | | | |
Collapse
|
33
|
Froltsov VA, Klüppel M, Raos G. Molecular dynamics simulation of rupture in glassy polymer bridges within filler aggregates. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:041801. [PMID: 23214604 DOI: 10.1103/physreve.86.041801] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 07/25/2012] [Indexed: 06/01/2023]
Abstract
We present a series of nonequilibrium molecular dynamics simulations, investigating the rupture mechanisms in glassy polymer films confined between two solid surfaces. Such systems provide a useful model for the strong nonlinear reinforcement of rubber by colloidal filler particles. Depending on the degree of confinement three qualitatively different rupture modes have been found, which originate from the interplay of internal (polymer-polymer) and external (polymer-wall) interactions. In very thin films we observe the formation and stretching of many single-chain bridges between the confining surfaces. Progressing to thicker samples we observe fewer bridges, consisting of bundled polymer chains, and eventually just one large bridge in thick specimens. The yield stress and the elongational modulus of the polymer films have been calculated from the stress-strain curves at various temperatures and confinements and their behavior has been analyzed in terms of polymer-polymer and polymer-surface interaction energies. The thinnest films (5 monomer diameters) are always glassy in our simulations, while the others display a glass transition temperature around 0.50-0.55 (in units ε(0)/k(B) of the Lennard-Jones interaction energy), depending on their thickness. This range of values, which has been determined using both the nonequilibrium tensile simulations and equilibrium diffusion data, agrees with the transition temperature previously found by shear simulations [Baljon and Robbins, Science 271, 482 (1996)].
Collapse
Affiliation(s)
- Vladimir A Froltsov
- Deutsches Institut für Kautschuktechnologie e.V., Eupener Strasse 33, D-30519 Hannover, Germany
| | | | | |
Collapse
|
34
|
Hudzinskyy D, Michels MAJ, Lyulin AV. Mechanical properties and local mobility of atactic-polystyrene films under constant-shear deformation. J Chem Phys 2012; 137:124902. [DOI: 10.1063/1.4754736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
35
|
Li C, Medvedev GA, Lee EW, Kim J, Caruthers JM, Strachan A. Molecular dynamics simulations and experimental studies of the thermomechanical response of an epoxy thermoset polymer. POLYMER 2012. [DOI: 10.1016/j.polymer.2012.07.026] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|