1
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Schneck C, Smrek J, Likos CN, Zöttl A. Supercoiled ring polymers under shear flow. NANOSCALE 2024. [PMID: 38639709 DOI: 10.1039/d3nr04258h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
We apply monomer-resolved computer simulations of supercoiled ring polymers under shear, taking full account of the hydrodynamic interactions, accompanied, in parallel, by simulations in which these are switched off. The combination of bending and torsional rigidities inherent in these polymers, in conjunction with hydrodynamics, has a profound impact on their flow properties. In contrast to their flexible counterparts, which dramatically deform and inflate under shear [Liebetreu et al., Commun. Mater. 2020, 1, 4], supercoiled rings undergo only weak changes in their overall shape and they display both a reduced propensity to tumbling (at fixed Weissenberg number) and a much stronger orientational resistance with respect to their flexible counterparts. In the presence of hydrodynamic interactions, the coupling of the polymer to solvent flow is capable of bringing about a topological transformation of writhe to twist at strong shear upon conservation of the overall linking number.
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Affiliation(s)
- Christoph Schneck
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
- Centro de Física de Materiales (CSIC, UPV/EHU) and Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
| | - Jan Smrek
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
| | - Christos N Likos
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
| | - Andreas Zöttl
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
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2
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Production and Application of Polymer Foams Employing Supercritical Carbon Dioxide. ADVANCES IN POLYMER TECHNOLOGY 2022. [DOI: 10.1155/2022/8905115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Polymeric foams have characteristics that make them attractive for different applications. However, some foaming methods rely on chemicals that are not environmentally friendly. One of the possibilities to tackle the environmental issue is to utilize supercritical carbon dioxide ScCO2 since it is a “green” solvent, thus facilitating a sustainable method of producing foams. ScCO2 is nontoxic, chemically inert, and soluble in molten plastic. It can act as a plasticizer, decreasing the viscosity of polymers according to temperature and pressure. Most foam processes can benefit from ScCO2 since the methods rely on nucleation, growth, and expansion mechanisms. Process considerations such as pretreatment, temperature, pressure, pressure drop, and diffusion time are relevant parameters for foaming. Other variables such as additives, fillers, and chain extenders also play a role in the foaming process. This review highlights the morphology, performance, and features of the foam produced with ScCO2, considering relevant aspects of replacing or introducing a novel foam. Recent findings related to foaming assisted by ScCO2 and how processing parameters influence the foam product are addressed. In addition, we discuss possible applications where foams have significant benefits. This review shows the recent progress and possibilities of ScCO2 in processing polymer foams.
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3
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Mostarac D, Kantorovich SS. Rheology of a Nanopolymer Synthesized through Directional Assembly of DNA Nanochambers, for Magnetic Applications. Macromolecules 2022; 55:6462-6473. [PMID: 35966117 PMCID: PMC9367010 DOI: 10.1021/acs.macromol.2c00738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/09/2022] [Indexed: 11/29/2022]
Abstract
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We present a numerical study of the effects of monomer
shape and
magnetic nature of colloids on the behavior of a single magnetic filament
subjected to the simultaneous action of shear flow and a stationary
external magnetic field perpendicular to the flow. We find that based
on the magnetic nature of monomers, magnetic filaments exhibit a completely
different phenomenology. Applying an external magnetic field strongly
inhibits tumbling only for filaments with ferromagnetic monomers.
Filament orientation with respect to the flow direction is in this
case independent of monomer shape. In contrast, reorientational dynamics
in filaments with superparamagnetic monomers are not inhibited by
applied magnetic fields, but enhanced. We find that the filaments
with spherical, superparamagnetic monomers, depending on the flow
and external magnetic field strength, assume semipersistent, collapsed,
coiled conformations, and their characteristic time of tumbling is
a function of field strength. However, external magnetic fields do
not affect the characteristic time of tumbling for filaments with
cubic, superparamagnetic monomers, but increase how often tumbling
occurs.
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Affiliation(s)
- Deniz Mostarac
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
- Research Platform MMM Mathematics-Magnetism-Materials, 1090 Vienna, Austria
| | - Sofia S. Kantorovich
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
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4
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Xu Q, Zhang J, Li X, van Duin DM, Hu Y, van Duin ACT, Ma T. How Polytetrafluoroethylene Lubricates Iron: An Atomistic View by Reactive Molecular Dynamics. ACS APPLIED MATERIALS & INTERFACES 2022; 14:6239-6250. [PMID: 35049265 DOI: 10.1021/acsami.1c23950] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The tribochemistry and transfer film formation at the metal/polymer interface plays an essential role in surface protection, wear reduction, and lubrication. Although the topic has been studied for decades, challenges persist in clarifying the nanoscale mechanism and dynamic evolution of tribochemical reactions. To investigate the tribochemistry between iron and polytetrafluoroethylene (PTFE) in ambient and cryogenic environments, we have trained and expanded a ReaxFF reactive force field to describe iron-oxygen-water-PTFE systems (C/H/O/F/Fe). Using ReaxFF molecular dynamics simulations, we find that mechanical shearing of single asperity induced the degradation of PTFE molecules and radicals, showing subsequent oxidation and hydroxylation reactions of the radicals initiated by C-C bond cleavage, in agreement with previous experimental observations. Furthermore, we studied mechanisms of interfacial tribochemical reactions and formation of transfer films. We found that tribochemical wear and Fe-C and Fe-F bonding networks are important mechanisms for anchoring molecular chains to form a transfer film on the iron countersurface. Hydroxyl groups can dehydrogenate to form short and strong chelation bonds with the Fe2O3 countersurface. A friction-induced oriented molecular layer plays a key role in reducing friction, which is responsible for the excellent lubrication property. By varying temperatures in the range of 10-300 K, we found a nonmonotonic change in friction with a maxima at 100 K. At cryogenic temperatures, the molecular mobility was obviously suppressed, while the chain rigidity was enhanced, resulting in the less oriented interface and brittle-like shear interface, which is responsible for nonmonotonic friction. This work elucidates mechanisms of tribochemical reactions and transfer film formation between iron and PTFE at the atomistic level, facilitating design and development of self-lubricating materials, especially under harsh conditions.
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Affiliation(s)
- Qiang Xu
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Jie Zhang
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Xin Li
- School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Diana M van Duin
- RxFF_Consulting LLC, State College, Pennsylvania 16801, United States
| | - Yuanzhong Hu
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Adri C T van Duin
- RxFF_Consulting LLC, State College, Pennsylvania 16801, United States
- Department of Mechanical Engineering, Pennsylvania State University, University Park, State College, Pennsylvania 16802, United States
| | - Tianbao Ma
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
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5
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Wang Y, Li J, Xie Y, Hu J, Zhu X, Sun S, Jing X, Mi HY, Liu C, Shen C. Fabrication of wrinkled thermoplastic polyurethane foams by dynamic supercritical carbon dioxide foaming. J Supercrit Fluids 2022. [DOI: 10.1016/j.supflu.2021.105429] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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6
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Chen W, Wei S. Compressive deformations of ring polymers in a confining channel. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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7
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Chen W, Kong X, Wei Q, Chen H, Liu J, Jiang D. Compression and Stretching of Confined Linear and Ring Polymers by Applying Force. Polymers (Basel) 2021; 13:polym13234193. [PMID: 34883696 PMCID: PMC8659573 DOI: 10.3390/polym13234193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022] Open
Abstract
We use Langevin dynamics to study the deformations of linear and ring polymers in different confinements by applying compression and stretching forces on their two sides. Our results show that the compression deformations are the results of an interplay among of polymer rigidity, degree of confinement, and force applied. When the applied force is beyond the threshold required for the buckling transition, the semiflexible chain under the strong confinement firstly buckles; then comes helical deformation. However, under the same force loading, the semiflexible chain under the weaker confinement exhibits buckling instability and shrinks from the folded ends/sides until it becomes three-folded structures. This happens because the strong confinement not only strongly reduces the buckling wavelength, but also increases the critical buckling force threshold. For the weakly confined polymers, in compression process, the flexible linear polymer collapses into condensed states under a small external force, whereas the ring polymer only shows slight shrinkage, due to the excluded volume interactions of two strands in the crowded states. These results are essential for understanding the deformations of the ring biomacromolecules and polymer chains in mechanical compression or driven transport.
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Affiliation(s)
- Wenduo Chen
- School of Materials, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China; (Q.W.); (H.C.); (J.L.); (D.J.)
- School of Materials, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen 518107, China
- Correspondence:
| | - Xiangxin Kong
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China;
| | - Qianqian Wei
- School of Materials, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China; (Q.W.); (H.C.); (J.L.); (D.J.)
- School of Materials, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen 518107, China
| | - Huaiyu Chen
- School of Materials, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China; (Q.W.); (H.C.); (J.L.); (D.J.)
- School of Materials, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen 518107, China
| | - Jiayin Liu
- School of Materials, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China; (Q.W.); (H.C.); (J.L.); (D.J.)
- School of Materials, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen 518107, China
| | - Dazhi Jiang
- School of Materials, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China; (Q.W.); (H.C.); (J.L.); (D.J.)
- School of Materials, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen 518107, China
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8
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Formanek M, Moreno AJ. Crowded solutions of single-chain nanoparticles under shear flow. SOFT MATTER 2021; 17:2223-2233. [PMID: 33465214 DOI: 10.1039/d0sm01978j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Single-chain nanoparticles (SCNPs) are ultrasoft objects obtained through purely intramolecular cross-linking of single polymer chains. By means of computer simulations with implemented hydrodynamic interactions, we investigate for the first time the effect of the shear flow on the structural and dynamic properties of SCNPs in semidilute and concentrated solutions. We characterize the dependence of several conformational and dynamic observables on the shear rate and the concentration, obtaining a set of power-law scaling laws. The concentration has a very different effect on the shear rate dependence of the former observables in SCNPs than in simple linear chains. Whereas for the latter the scaling behaviour is marginally dependent on the concentration, two clearly different scaling regimes are found for the SCNPs below and above the overlap concentration. At fixed shear rate SCNPs and linear chains also respond very differently to crowding. Whereas, at moderate and high Weissenberg numbers the linear chains swell, the SCNPs exhibit a complex non-monotonic behaviour. We suggest that these findings are inherently related to the topological interactions preventing concatenation of the SCNPs, which lead to less interpenetration than for linear chains, and to the limitation to stretching imposed by the permanent cross-links in the SCNPs, which itself limits the ways to spatially arrange in the shear flow.
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Affiliation(s)
- Maud Formanek
- Centro de Física de Materiales (CSIC, UPV/EHU) and Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain. and Sainsbury Laboratory, University of Cambridge, 47 Bateman Street, Cambridge CB2 1LR, UK
| | - Angel J Moreno
- Centro de Física de Materiales (CSIC, UPV/EHU) and Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain. and Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018 San Sebastián, Spain
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9
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Kong XX, Chen WD, Cui FC, Li YQ. Conformational and Dynamical Evolution of Block Copolymers in Shear Flow. CHINESE JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1007/s10118-021-2523-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Wu Q, Gou S, Fei Y, Yang X, Liu M, Huang J. Self-Assembly Supramolecular Systems Based on Guanidinium Salts Modified Hyperbranched Polyamidoamine and Cationic Acrylamide Copolymers. Polymers (Basel) 2019; 11:E1781. [PMID: 31683531 PMCID: PMC6918400 DOI: 10.3390/polym11111781] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/24/2019] [Accepted: 10/25/2019] [Indexed: 12/02/2022] Open
Abstract
Herein, novel hyperbranched polyamidoamine guanidinium salts (GS-h-PAMAM) and two cationic acrylamide copolymers P(AM-DAC-ABSM) and P(AM-DAC-AMTU) were successfully prepared. Then, self-assembly supramolecular systems were synthesized by directly mixing GS-h-PAMAM with copolymers in aqueous solution, and the mechanism of the self-assembly process was speculated. FT-IR, NMR, and SEM were used for structural confirmation. Furthermore, the excellent solution properties revealed that the supramolecular systems had potential application in clay hydration inhibitors. More importantly, utilizing functionalized hyperbranched polyamidoamine in the synthesis self-assembly supramolecular systems was an effective strategy for expanding their application fields and developing new functional materials, providing a powerful reference for the next study.
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Affiliation(s)
- Qi Wu
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China.
- Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, China.
| | - Shaohua Gou
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China.
| | - Yumei Fei
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China.
| | - Xiaoyan Yang
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China.
| | - Mengyu Liu
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China.
| | - Jinglun Huang
- Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, China.
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11
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Role of Hydrodynamic Interactions in the Deformation of Star Polymers in Poiseuille Flow. CHINESE JOURNAL OF POLYMER SCIENCE 2019. [DOI: 10.1007/s10118-020-2346-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Wang Z, Zhai Q, Chen W, Wang X, Lu Y, An L. Mechanism of Nonmonotonic Increase in Polymer Size: Comparison between Linear and Ring Chains at High Shear Rates. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00809] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Zhenhua Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
- University of Science and Technology of China, Hefei 230026, P. R. China
| | - Qilong Zhai
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
- School of Mathematical Sciences, Peking University, Beijing 100871, P. R. China
| | - Wei Chen
- School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Xiaoliang Wang
- School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Yuyuan Lu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
| | - Lijia An
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
- University of Science and Technology of China, Hefei 230026, P. R. China
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13
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Kong X, Han Y, Chen W, Cui F, Li Y. Understanding conformational and dynamical evolution of semiflexible polymers in shear flow. SOFT MATTER 2019; 15:6353-6361. [PMID: 31298682 DOI: 10.1039/c9sm00600a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A clear description of the conformational and dynamical evolution of polymer chains in shear flow is the fundamental basis of microfluidic separations and macroscopic rheological behaviors. We employ graph theory analysis to analyze the local deformation and dynamics of linear polymer chains with different rigidities in shear flow based on the simulation trajectories that record the instantaneous conformations and dynamics. Our results show that all semiflexible chains experience quasi-periodic tumbling motions when the shear strain overwhelms the U-shape (or S-shape) deformation energy barrier. More interestingly, the contact map provides solid evidence for the asymmetric deformation in the whole tumbling motion. In the stretching process: at small and intermediate shear strength, flexible polymers show a quasi-affine deformation while semiflexible ones are initially unfolded from the center of the chains, then both of them follow the extension with half dumbbell- or dumbbell-like ends; at high shear strength, all polymer chains present only a dumbbell-like extension. In the collapse process, all chains prefer to initiate the folding from chain ends. This finding can facilitate our understanding on how semiflexible polymer chains relax and dissipate the stress in shear flow.
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Affiliation(s)
- Xiangxin Kong
- Key Laboratory of High-Performance Synthetic Rubber and Its Composite Materials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, P. R. China.
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14
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Lin Y, Zhang Y, Wang Z, Craig SL. Dynamic Memory Effects in the Mechanochemistry of Cyclic Polymers. J Am Chem Soc 2019; 141:10943-10947. [DOI: 10.1021/jacs.9b03564] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Yangju Lin
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Yudi Zhang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Zi Wang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Stephen L. Craig
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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15
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Young CD, Qian JR, Marvin M, Sing CE. Ring polymer dynamics and tumbling-stretch transitions in planar mixed flows. Phys Rev E 2019; 99:062502. [PMID: 31330603 DOI: 10.1103/physreve.99.062502] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Indexed: 06/10/2023]
Abstract
The properties of dilute polymer solutions are governed by the conformational dynamics of individual polymers which can be perturbed in the presence of an applied flow. Much of our understanding of dilute solutions comes from studying how flows manipulate the molecular features of polymer chains out of equilibrium, primarily focusing on linear polymer chains. Recently there has been an emerging interest in the dynamics of nonlinear architectures, particularly ring polymers, which exhibit surprising out-of-equilibrium dynamics in dilute solutions. In particular, it has been observed that hydrodynamics can couple to topology in planar elongational and shear flows, driving molecular expansion in the nonflow direction that is not observed for linear chains. In this paper, we extend our understanding of dilute ring polymer dynamics to mixed flows, which represent flow profiles intermediate between simple shear or planar elongation. We map the conformational behaviors at a number of flow geometries and strengths, demonstrating transitions between coiled, tumbling, and stretched regimes. Indeed, these observations are consistent with how linear chains respond to mixed flows. For both linear and ring polymers, we observe a marked first-order-like transition between tumbling and stretched polymers that we attribute to a dynamic energy barrier between the two states. This manifests as bimodal extension distributions in a narrow range of flow strengths and geometries, with the primary difference between rings and linear chains being the presence of molecular expansion in the vorticity direction.
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Affiliation(s)
- Charles D Young
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - June R Qian
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | | | - Charles E Sing
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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16
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Affiliation(s)
- Maud Formanek
- Centro de Física
de Materiales (CSIC, UPV/EHU) and Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
| | - Angel J. Moreno
- Centro de Física
de Materiales (CSIC, UPV/EHU) and Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Donostia International
Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018 San Sebastián, Spain
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17
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Zhang JZ, Peng XY, Liu S, Jiang BP, Ji SC, Shen XC. The Persistence Length of Semiflexible Polymers in Lattice Monte Carlo Simulations. Polymers (Basel) 2019; 11:E295. [PMID: 30960279 PMCID: PMC6419224 DOI: 10.3390/polym11020295] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/01/2019] [Accepted: 02/05/2019] [Indexed: 01/10/2023] Open
Abstract
While applying computer simulations to study semiflexible polymers, it is a primary task to determine the persistence length that characterizes the chain stiffness. One frequently asked question concerns the relationship between persistence length and the bending constant of applied bending potential. In this paper, theoretical persistence lengths of polymers with two different bending potentials were analyzed and examined by using lattice Monte Carlo simulations. We found that the persistence length was consistent with theoretical predictions only in bond fluctuation model with cosine squared angle potential. The reason for this is that the theoretical persistence length is calculated according to a continuous bond angle, which is discrete in lattice simulations. In lattice simulations, the theoretical persistence length is larger than that in continuous simulations.
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Affiliation(s)
- Jing-Zi Zhang
- State Key Laboratory for Chemistry and Molecular Engineering of Medical Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
| | - Xiang-Yao Peng
- State Key Laboratory for Chemistry and Molecular Engineering of Medical Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
| | - Shan Liu
- State Key Laboratory for Chemistry and Molecular Engineering of Medical Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
| | - Bang-Ping Jiang
- State Key Laboratory for Chemistry and Molecular Engineering of Medical Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
| | - Shi-Chen Ji
- State Key Laboratory for Chemistry and Molecular Engineering of Medical Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
| | - Xing-Can Shen
- State Key Laboratory for Chemistry and Molecular Engineering of Medical Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
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18
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Liu L, Chen J, An L. Individual circular polyelectrolytes under shear flow. J Chem Phys 2018; 149:163316. [PMID: 30384673 DOI: 10.1063/1.5028406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Individual circular polyelectrolytes in simple shear flow are studied by means of mesoscale hydrodynamic simulations, revealing the complex coupling effects of shear rate, electrostatic interaction, and circular architecture on their conformational and dynamical properties. Shear flow deforms the polyelectrolyte and strips condensed counterions from its backbone. A decrease in condensed counterions alters electrostatic interactions among charged particles, affecting shear-induced polymer deformation and orientation. Circular architecture determines the features of deformation and orientation. At weak electrostatic interaction strengths, the polyelectrolyte changes its shape from an oblate ring at small shear rates to a prolate ring at large shear rates, whereas strong electrostatic interaction strengths are associated with a transition from a prolate coil to a prolate ring. Circular polyelectrolytes exhibit tumbling and tank-treading motions in the range of large shear rates. Further study reveals a similarity between the roles of intramolecular electrostatic repulsion and chain rigidity in shear-induced dynamics.
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Affiliation(s)
- Lijun Liu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China
| | - Jizhong Chen
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China
| | - Lijia An
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China
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19
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Jaramillo-Cano D, Formanek M, Likos CN, Camargo M. Star Block-Copolymers in Shear Flow. J Phys Chem B 2018; 122:4149-4158. [PMID: 29547293 DOI: 10.1021/acs.jpcb.7b12229] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Star block-copolymers (SBCs) have been demonstrated to constitute self-assembling building blocks with specific softness, functionalization, shape, and flexibility. In this work, we study the behavior of an isolated SBC under a shear flow by means of particle-based multiscale simulations. We systematically analyze the conformational properties of low-functionality stars, as well as the formation of attractive patches on their corona as a function of the shear rate. We cover a wide range of system parameters, including functionality, amphiphilicity, and solvent quality. It is shown that SBCs display a richer structural and dynamical behavior than athermal star polymers in a shear flow [ Ripoll Phys. Rev. Lett. , 2006 , 96 , 188302 ], and, therefore, they are also interesting candidates to tune the viscoelastic properties of complex fluids. We identify three factors of patch reorganization under shear that lead to patch numbers and orientations depending on the shear rate, namely, free arms joining existing patches, fusion of medium-sized patches into bigger ones, and fission of large patches into two smaller ones under high shear rates. Because the conformation of single SBC is expected to be preserved in low-density bulk phases, the presented results are a first step in understanding and predicting the rheological properties of semidilute suspensions of this kind of polymers.
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Affiliation(s)
- Diego Jaramillo-Cano
- Faculty of Physics , University of Vienna , Boltzmanngasse 5 , A-1090 Vienna , Austria
| | - Maud Formanek
- Faculty of Physics , University of Vienna , Boltzmanngasse 5 , A-1090 Vienna , Austria
| | - Christos N Likos
- Faculty of Physics , University of Vienna , Boltzmanngasse 5 , A-1090 Vienna , Austria
| | - Manuel Camargo
- Centro de Investigaciones en Ciencias Básicas y Aplicadas , Universidad Antonio Nariño , Km 18 via Cali-Jamundí , 760030 Cali , Colombia
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20
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Xu X, Chen J, An L. Probing relationship between structure and viscosity of unentangled polymers in steady shear flow. Sci China Chem 2017. [DOI: 10.1007/s11426-017-9129-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Liu L, Chen W, Chen J. Shape and Diffusion of Circular Polyelectrolytes in Salt-Free Dilute Solutions and Comparison with Linear Polyelectrolytes. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00189] [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)
- Lijun Liu
- State Key Laboratory
of Polymer
Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
| | - Wenduo Chen
- State Key Laboratory
of Polymer
Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
| | - Jizhong Chen
- State Key Laboratory
of Polymer
Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
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22
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Xu X, Chen J. Structural Mechanism for Viscosity of Semiflexible Polymer Melts in Shear Flow. ACS Macro Lett 2017; 6:331-336. [PMID: 35610868 DOI: 10.1021/acsmacrolett.6b00979] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The viscosities of semiflexible polymers with different chain stiffnesses in shear flow are studied via nonequilibrium molecular dynamics techniques. The simulation reproduces the experimentally observed results, giving a complete picture of viscosity as chain stiffness increases. Analysis of flow-induced changes in chain conformation and local structure indicates two distinct mechanisms behind a variety of viscosity curves. For polymers of small stiffnesses, it is related to flow-induced changes in chain conformation and, for those of large stiffnesses, to flow-induced instabilities of nematic structures. The four-region flow curve is confirmed for polymers of contour length close to persistence length and understood by combining the two structural mechanisms. Thus, these findings clarify the microscopic structures indicated by the macroscopic viscosity.
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Affiliation(s)
- Xiaolei Xu
- State Key Laboratory
of Polymer
Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People’s Republic of China
| | - Jizhong Chen
- State Key Laboratory
of Polymer
Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People’s Republic of China
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23
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Chen W, Zhang K, Liu L, Chen J, Li Y, An L. Conformation and Dynamics of Individual Star in Shear Flow and Comparison with Linear and Ring Polymers. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02636] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Kexin Zhang
- School
of Environmental Science, Northeast Normal University, 5268 Renmin
Street, Changchun, P. R. China 130024
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24
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Coil-helix-globule transition for self-attractive semiflexible ring chains. POLYMER 2017. [DOI: 10.1016/j.polymer.2016.12.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Xu X, Chen J. Effect of functionality on unentangled star polymers at equilibrium and under shear flow. J Chem Phys 2016; 144:244905. [DOI: 10.1063/1.4955098] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Xiaolei Xu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Jilin, Changchun 130022, People’s Republic of China
| | - Jizhong Chen
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Jilin, Changchun 130022, People’s Republic of China
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Yamamoto T, Tezuka Y. Cyclic polymers revealing topology effects upon self-assemblies, dynamics and responses. SOFT MATTER 2015; 11:7458-7468. [PMID: 26264187 DOI: 10.1039/c5sm01557j] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A variety of single- and multicyclic polymers having programmed chemical structures with guaranteed purity have now become obtainable owing to a number of synthetic breakthroughs achieved in recent years. Accordingly, a broadening range of studies has been undertaken to gain updated insights on fundamental polymer properties of cyclic polymers in either solution or bulk, in either static or dynamic states, and in self-assemblies, leading to unusual properties and functions of polymer materials based on their cyclic topologies. In this article, we review recent studies aiming to achieve distinctive properties and functions by cyclic polymers unattainable by their linear or branched counterparts. We focus, in particular, on selected examples of unprecedented topology effects of cyclic polymers upon self-assemblies, dynamics and responses, to highlight current progress in Topological Polymer Chemistry.
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Affiliation(s)
- Takuya Yamamoto
- Department of Organic and Polymeric Materials, Graduate School of Science and Engineering, Tokyo Institute of Technology, Tokyo, 152-8552, Japan.
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Chen W, Zhao H, Liu L, Chen J, Li Y, An L. Effects of excluded volume and hydrodynamic interaction on the deformation, orientation and motion of ring polymers in shear flow. SOFT MATTER 2015; 11:5265-5273. [PMID: 26053427 DOI: 10.1039/c5sm00837a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A ring polymer is a classical model to explore the behaviors of biomacromolecules. Compared with its linear counterpart in shear flow, the ring polymer should be more sensitive to excluded volume and hydrodynamic interaction attributed to the absence of chain ends. We carried out multiparticle collision dynamics combined with molecular dynamics simulation to study the effects of excluded volume and hydrodynamic interaction on the behaviors of ring polymers in shear flow. The results show that in the absence of the strong excluded volume interaction, the ring polymer prefers a two-strand linear conformation with high deformation and orientation in the flow-gradient plane, and the tank-treading motion is nearly negligible. Ring polymers without excluded volume show no significant difference from linear polymers in the scaling exponents for the deformation, orientation and tumbling motion. We also observed that the hydrodynamic interaction could efficiently slow down the relaxation of ring polymers while the scaling exponents against the Weissenberg number have rarely been affected.
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Affiliation(s)
- Wenduo Chen
- Key Laboratory of Synthetic Rubber & Laboratory of Advanced Power Sources, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, P. R. China130022.
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28
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Chen W, Li Y, Zhao H, Liu L, Chen J, An L. Conformations and dynamics of single flexible ring polymers in simple shear flow. POLYMER 2015. [DOI: 10.1016/j.polymer.2015.03.034] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Xu X, Chen J, An L. Shear thinning behavior of linear polymer melts under shear flow via nonequilibrium molecular dynamics. J Chem Phys 2015; 140:174902. [PMID: 24811663 DOI: 10.1063/1.4873709] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The properties of both untangled and entangled linear polymer melts under shear flow are studied by nonequilibrium molecular dynamics simulations. The results reveal that the dependence of shear viscosity η on shear rate γ, expressed by n ~ γ(-n), exhibits three distinct regimes. The first is the well-known Newtonian regime, namely, η independent of shear rate at small shear rates γ < τ0(-1) (where τ0 is the longest polymer relaxation time at equilibrium). In the non-Newtonian regime (γ > τ0(-1)) the shear dependence of viscosity exhibits a crossover at a critical shear rate γc dividing this regime into two different regimes, shear thinning regime I (ST-I) and II (ST-II), respectively. In the ST-I regime (τ0(-1) < γ < γc), the exponent n increases with increasing chain length N, while in the ST-II regime (γ > γc) a universal power law n ~ γ(-0.37) is found for considered chain lengths. Furthermore, the longer the polymer chain is, the smaller the shear viscosity for a given shear rate in the ST-II regime. The simulation also shows that a characteristic chain length, below which γc will be equal to τ0(-1), lies in the interval 30 < N < 50. For all considered chain lengths in the ST-II regime, we also find that the first and second normal stress differences N1 and N2 follow power laws of N1 ~ γ(2/3) and N2 ~ γ(0.82), respectively; the orientation resistance parameter mG follows the relation mG ~ γ(0.75) and the tumbling frequency ftb follows ftb ~ γ(0.75). These results imply that the effects of entanglement on the shear dependences of these properties may be negligible in the ST-II regime. These findings may shed some light on the nature of shear thinning in flexible linear polymer melts.
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Affiliation(s)
- Xiaolei Xu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China
| | - Jizhong Chen
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China
| | - Lijia An
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China
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30
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Xu X, Chen J, An L. Simulation studies on architecture dependence of unentangled polymer melts. J Chem Phys 2015; 142:074903. [DOI: 10.1063/1.4908262] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Xiaolei Xu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People’s Republic of China
| | - Jizhong Chen
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People’s Republic of China
| | - Lijia An
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People’s Republic of China
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31
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Dolgushev M, Guérin T, Blumen A, Bénichou O, Voituriez R. Gaussian semiflexible rings under angular and dihedral restrictions. J Chem Phys 2014; 141:014901. [PMID: 25005305 DOI: 10.1063/1.4885445] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Semiflexible polymer rings whose bonds obey both angular and dihedral restrictions [M. Dolgushev and A. Blumen, J. Chem. Phys. 138, 204902 (2013)], are treated under exact closure constraints. This allows us to obtain semianalytic results for their dynamics, based on sets of Langevin equations. The dihedral restrictions clearly manifest themselves in the behavior of the mean-square monomer displacement. The determination of the equilibrium ring conformations shows that the dihedral constraints influence the ring curvature, leading to compact folded structures. The method for imposing such constraints in Gaussian systems is very general and it allows to account for heterogeneous (site-dependent) restrictions. We show it by considering rings in which one site differs from the others.
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Affiliation(s)
- Maxim Dolgushev
- Theoretical Polymer Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Thomas Guérin
- Laboratoire de Physique Théorique de la Matière Condensée, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, 4 Place Jussieu, 75005 Paris, France
| | - Alexander Blumen
- Theoretical Polymer Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Olivier Bénichou
- Laboratoire de Physique Théorique de la Matière Condensée, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, 4 Place Jussieu, 75005 Paris, France
| | - Raphaël Voituriez
- Laboratoire de Physique Théorique de la Matière Condensée, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, 4 Place Jussieu, 75005 Paris, France
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32
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Suzuki T, Yamamoto T, Tezuka Y. Constructing a Macromolecular K3,3 Graph through Electrostatic Self-Assembly and Covalent Fixation with a Dendritic Polymer Precursor. J Am Chem Soc 2014; 136:10148-55. [DOI: 10.1021/ja504891x] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Takuya Suzuki
- Department
of Organic and
Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Takuya Yamamoto
- Department
of Organic and
Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Yasuyuki Tezuka
- Department
of Organic and
Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
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33
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Diffusion behavior of polyelectrolytes in dilute solution: coupling effects of hydrodynamic and Coulomb interactions. Sci China Chem 2014. [DOI: 10.1007/s11426-014-5125-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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34
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35
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Lang PS, Obermayer B, Frey E. Dynamics of a semiflexible polymer or polymer ring in shear flow. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:022606. [PMID: 25353501 DOI: 10.1103/physreve.89.022606] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Indexed: 06/04/2023]
Abstract
Polymers exposed to shear flow exhibit a remarkably rich tumbling dynamics. While rigid rods rotate on Jeffery orbits, a flexible polymer stretches and coils up during tumbling. Theoretical results show that in both of these asymptotic regimes the corresponding tumbling frequency f(c) in a linear shear flow of strength γ scales as a power law Wi(2/3) in the Weissenberg number Wi = γτ, where τ is a characteristic time of the polymer's relaxational dynamics. For a flexible polymer these theoretical results are well confirmed by a large body of experimental single molecule studies. However, for the intermediate semiflexible regime, especially relevant for cytoskeletal filaments like F-actin and microtubules, the situation is less clear. While recent experiments on single F-actin filaments are still interpreted within the classical Wi(2/3) scaling law, theoretical results indicated deviations from it. Here we perform extensive Brownian dynamics simulations to explore the tumbling dynamics of semiflexible polymers over a broad range of shear strength and the polymer's persistence length l(p). We find that the Weissenberg number alone does not suffice to fully characterize the tumbling dynamics, and the classical scaling law breaks down. Instead, both the polymer's stiffness and the shear rate are relevant control parameters. Based on our Brownian dynamics simulations we postulate that in the parameter range most relevant for cytoskeletal filaments there is a distinct scaling behavior with f(c) τ* = Wi(3/4)f(c)(x) with Wi = γτ* and the scaling variable x = (l(p)/L)(Wi)(-1/3); here τ* is the time the polymer's center of mass requires to diffuse its own contour length L. Comparing these results with experimental data on F-actin we find that the Wi(3/4) scaling law agrees quantitatively significantly better with the data than the classical Wi(2/3) law. Finally, we extend our results to single ring polymers in shear flow, and find similar results as for linear polymers with slightly different power laws.
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Affiliation(s)
- Philipp S Lang
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Department of Physics, Ludwig-Maximilians-Universität München, Theresienstrasse 37, D-80333 Munich, Germany and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität München, Schellingstraße 4, D-80333 Munich, Germany
| | - Benedikt Obermayer
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Department of Physics, Ludwig-Maximilians-Universität München, Theresienstrasse 37, D-80333 Munich, Germany
| | - Erwin Frey
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Department of Physics, Ludwig-Maximilians-Universität München, Theresienstrasse 37, D-80333 Munich, Germany and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität München, Schellingstraße 4, D-80333 Munich, Germany
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36
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Zhang H, Lin Y, Xu Y, Weng W. Mechanochemistry of Topological Complex Polymer Systems. Top Curr Chem (Cham) 2014; 369:135-207. [PMID: 25791486 DOI: 10.1007/128_2014_617] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Although existing since the concept of macromolecules, polymer mechanochemistry is a burgeoning field which attracts great scientific interest in its ability to bias conventional reaction pathways and its potential to fabricate mechanoresponsive materials. We review here the effect of topology on the mechanical degradation of polymer chains and the activation of mechanophores in polymer backbones. The chapter focuses on both experimental and theoretical work carried out in the past 70 years. After a general introduction (Sect. 1), where the concept, the history, and the application of polymer mechanochemistry are briefly described, flow fields to study polymer mechanochemistry are discussed (Sect. 2), results of mechanochemistry study are presented for linear polymers (Sect. 3), cyclic polymers (Sect. 4), graft polymers (Sect. 5), star-shaped polymers (Sect. 6), hyperbranched polymers and dendrimers (Sect. 7), and systems with dynamic topology (Sect. 8). Here we focus on (1) experimental results involving the topological effect on the coil-to-stretch transition and the fracture of the polymer chains, (2) the underlying mechanisms and the key factor that determines the mechanical stability of the macromolecules, (3) theoretical models that relate to the experimental observations, and (4) rational design of mechanophores in complex topology to achieve multiple activations according to the existing results observed in chain degradation.
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Affiliation(s)
- Huan Zhang
- Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, P. R. China
| | - Yangju Lin
- Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, P. R. China
| | - Yuanze Xu
- Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, P. R. China
| | - Wengui Weng
- Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, P. R. China.
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