1
|
Ji S, Zhao S, Qiao D, Xu Y, Jia C, Niu M, Zhang B. Controlling sodium chloride concentration modulates the supramolecular structure and sol features of wheat starch-acetylated starch binary matrix. Carbohydr Polym 2024; 335:122072. [PMID: 38616094 DOI: 10.1016/j.carbpol.2024.122072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/25/2024] [Accepted: 03/15/2024] [Indexed: 04/16/2024]
Abstract
The sol performance of wheat starch (WS) matrix incorporating acetylated starch (AS) is crucial for the processing and quality features of wheat products. From a supramolecular structure view, how regulating salt (sodium chloride) concentration modulates the sol features, e.g., pasting, zero-shear viscosity (ZSV) and thixotropy of WS-AS binary matrix was explored. Compared to the salt-free counterpart, the saline matrices exhibited a delayed pasting profile and a decreased viscoelasticity. Thereinto, the sol at 0.02 M NaCl exhibited the smallest ZSV (23,710 Pa·s) and the greatest in-shear recovery ratio (33.7 %). Such variations could be attributed to the weakened coil-helix, nematic-smectic and isotropy-anisotropy transitions from a side-chain liquid-crystalline perspective. Meanwhile, the correlation length (ξ) and radius of gyration (Rg) obtained from small angle X-ray scattering analysis were increased by 5.2 and 9.6 Å respectively, which disclosed a restrained entanglement and an enhanced chain mobility. These results would provide a reference for the design of fluid/semisolid products with optimized qualities.
Collapse
Affiliation(s)
- Shengsong Ji
- College of Food Science, Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing, Modern"Chuan cai Yu wei" Food Industry Innovation Research Institute, Southwest University, Chongqing 400715, China; College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Siming Zhao
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Dongling Qiao
- College of Food Science, Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing, Modern"Chuan cai Yu wei" Food Industry Innovation Research Institute, Southwest University, Chongqing 400715, China
| | - Yan Xu
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Caihua Jia
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Meng Niu
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Binjia Zhang
- College of Food Science, Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing, Modern"Chuan cai Yu wei" Food Industry Innovation Research Institute, Southwest University, Chongqing 400715, China.
| |
Collapse
|
2
|
Smith L, Karimi-Varzaneh HA, Finger S, Giunta G, Troisi A, Carbone P. Framework for a High-Throughput Screening Method to Assess Polymer/Plasticizer Miscibility: The Case of Hydrocarbons in Polyolefins. Macromolecules 2024; 57:4637-4647. [PMID: 38827962 PMCID: PMC11140736 DOI: 10.1021/acs.macromol.3c01764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 04/26/2024] [Accepted: 04/30/2024] [Indexed: 06/05/2024]
Abstract
Polymer composite materials require softening to reduce their glass transition temperature and improve processability. To this end, plasticizers (PLs), which are small organic molecules, are added to the polymer matrix. The miscibility of these PLs has a large impact on their effectiveness and, therefore, their interactions with the polymer matrix must be carefully considered. Many PL characteristics, including their size, topology, and flexibility, can impact their miscibility and, because of the exponentially large number of PLs, the current trial-and-error approach is very ineffective. In this work, we show that using coarse-grained molecular simulations of a small dataset of 48 PLs, it is possible to identify topological and thermodynamic descriptors that are proxy for their miscibility. Using ad-hoc molecular dynamics simulation setups that are relatively computationally inexpensive, we establish correlations between the PLs' topology, internal flexibility, thermodynamics of aggregation, and degree of miscibility, and use these descriptors to classify the molecules as miscible or immiscible. With all available data, we also construct a decision tree model, which achieves a F1 score of 0.86 ± 0.01 with repeated, stratified 5-fold cross-validation, indicating that this machine learning method can be a promising route to fully automate the screening. By evaluating the individual performance of the descriptors, we show this procedure enables a 10-fold reduction of the test space and provides the basis for the development of workflows that can efficiently screen PLs with a variety of topological features. The approach is used here to screen for apolar PLs in polyisoprene melts, but similar proxies would be valid for other polyolefins, while, in cases where polar interactions drive the miscibility, other descriptors are likely to be needed.
Collapse
Affiliation(s)
- Lois Smith
- Department
of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13
9PL Manchester, U.K.
| | | | - Sebastian Finger
- Continental
Reifen Deutschland GmbH, Jädekamp 30, D-30419 Hanover, Germany
| | - Giuliana Giunta
- Department
of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13
9PL Manchester, U.K.
- BASF, Carl-Bosch-Strasse 38, 67056 Ludwigshafen, Germany
| | - Alessandro Troisi
- Department
of Chemistry, University of Liverpool, Crown Street, L69 7ZD Liverpool, U.K.
| | - Paola Carbone
- Department
of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13
9PL Manchester, U.K.
- Department
of Chemistry, The University of Manchester, Oxford Road, M13 9PL Manchester, U.K.
| |
Collapse
|
3
|
Yan R, Zhao C, Zhao N. Attractive crowding effect on passive and active polymer looping kinetics. J Chem Phys 2024; 160:134902. [PMID: 38568946 DOI: 10.1063/5.0199023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 03/19/2024] [Indexed: 04/05/2024] Open
Abstract
Loop formation in complex environments is crucially important to many biological processes in life. In the present work, we adopt three-dimensional Langevin dynamics simulations to investigate passive and active polymer looping kinetics in crowded media featuring polymer-crowder attraction. We find polymers undergo a remarkable coil-globule-coil transition, highlighted by a marked change in the Flory scaling exponent of the gyration radius. Meanwhile, looping time as a function of the crowder's volume fraction demonstrates an apparent non-monotonic alteration. A small number of crowders induce a compact structure, which largely facilitates the looping process. While a large number of crowders heavily impede end-to-end diffusion, looping kinetics is greatly inhibited. For a self-propelled chain, we find that the attractive crowding triggers an unusual activity effect on looping kinetics. Once a globular state is formed, activity takes an effort to open the chain from the compact structure, leading to an unexpected activity-induced inhibition of looping. If the chain maintains a coil state, the dominant role of activity is to enhance diffusivity and, thus, speed up looping kinetics. The novel conformational change and looping kinetics of both passive and active polymers in the presence of attractive crowding highlight a rather distinct scenario that has no analogy in a repulsive crowding counterpart. The underlying mechanism enriches our understanding of the crucial role of attractive interactions in modulating polymer structure and dynamics.
Collapse
Affiliation(s)
- Ran Yan
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Chaonan Zhao
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Nanrong Zhao
- College of Chemistry, Sichuan University, Chengdu 610064, China
| |
Collapse
|
4
|
Khan RAA, Luo M, Alsaad AM, Qattan IA, Abedrabbo S, Hua D, Zulfqar A. The Role of Polymer Chain Stiffness and Guest Nanoparticle Loading in Improving the Glass Transition Temperature of Polymer Nanocomposites. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1896. [PMID: 37446412 DOI: 10.3390/nano13131896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 07/15/2023]
Abstract
The impact of polymer chain stiffness characterized by the bending modulus (kθ) on the glass transition temperature (Tg) of pure polymer systems, as well as polymer nanocomposites (PNCs), is investigated using molecular dynamics simulations. At small kθ values, the pure polymer system and respective PNCs are in an amorphous state, whereas at large kθ values, both systems are in a semicrystalline state with a glass transition at low temperature. For the pure polymer system, Tg initially increases with kθ and does not change obviously at large kθ. However, the Tg of PNCs shows interesting behaviors with the increasing volume fraction of nanoparticles (fNP) at different kθ values. Tg tends to increase with fNP at small kθ, whereas it becomes suppressed at large kθ.
Collapse
Affiliation(s)
- Raja Azhar Ashraaf Khan
- Department of Physics, Zhejiang Normal University, Jinhua 321004, China
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Mengbo Luo
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Ahmad M Alsaad
- Department of Physics, Jordan University of Science & Technology, P.O. Box 3030, Irbid 22110, Jordan
| | - Issam A Qattan
- Department of Physics, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi 127788, United Arab Emirates
| | - Sufian Abedrabbo
- Department of Physics, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi 127788, United Arab Emirates
| | - Daoyang Hua
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Afsheen Zulfqar
- Department of Physics, Zhejiang Normal University, Jinhua 321004, China
| |
Collapse
|
5
|
Giunta G, Smith L, Bartha K, Karimi-Varzaneh HA, Carbone P. Understanding the balance between additives' miscibility and plasticisation effect in polymer composites: a computational study. SOFT MATTER 2023; 19:2377-2384. [PMID: 36920461 DOI: 10.1039/d2sm01642g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Plasticisers are small organic molecules routinely added to polymer composites that modify the processability of the compounds by adsorbing on the filler's surface or dispersing into the polymer matrix. Here using a simple yet chemically specific coarse-grained model, we demonstrate that the filler surface coverage and the degree of dispersion into the polymer matrix can be tuned without modifying the chemistry of the plasticisers but only by varying their conformational flexibility. We show that when the adsorption mechanism and clustering into the bulk are entropically driven as in this work, this is a general phenomenon independent on the polymer chemistry and its molecular weight. Our findings suggest a simple practical design rule that requires only minor modifications of the plasticisers' chemistry to achieve maximum adsorption onto the filler surface or dispersion into the polymer matrix.
Collapse
Affiliation(s)
- Giuliana Giunta
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| | - Lois Smith
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| | - Kristof Bartha
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| | | | - Paola Carbone
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| |
Collapse
|
6
|
Qu J, Chen Q, Huang W, Zhang L, Liu J. Dispersion and Diffusion Mechanism of Nanofillers with Different Geometries in Bottlebrush Polymers: Insights from Molecular Dynamics Simulation. J Phys Chem B 2022; 126:7761-7770. [PMID: 36169228 DOI: 10.1021/acs.jpcb.2c04389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dispersion and diffusion mechanism of nanofillers in polymer nanocomposites (PNCs) are crucial for understanding the properties of PNCs, which is of great significance for the design of novel materials. Herein, we investigate the dispersion and diffusion behavior of two geometries of nanofillers, namely, spherical nanoparticles (SNPs) and nanorods (NRs), in bottlebrush polymers by utilizing coarse-grained molecular dynamics simulations. With the increase of the interaction strength between the nanofiller and polymer (εnp), both the SNPs and NRs experience a typical "aggregated phase-dispersed phase-bridged phase" state transition in the bottlebrush polymer matrix. We evaluate the validity of the Stokes-Einstein (SE) equation for predicting the diffusion coefficient of nanofillers in bottlebrush polymers. The results demonstrate that the SE predictions are slightly larger than the simulated values for small SNP sizes because the local viscosity that is felt by small SNPs in the densely grafted bottlebrush polymer does not differ much from the macroscopic viscosity. The relative size of the length of the NRs (L) and the radius of gyration (Rg) of the bottlebrush polymer play a key role in the diffusion of NRs. In addition, we characterize the anisotropic diffusion of NRs to analyze their translational and rotational diffusion. The motion of NRs in the direction perpendicular to the end-to-end vector is more hindered, indicating that there is a strong coupling between the rotation of NRs and the motion of the polymer. The NR motion shows stronger anisotropic diffusion at short time scales because of the steric effects generated by side chains of the bottlebrush polymer. In general, our results provide a fundamental understanding of the dispersion of nanofillers and the microscopic mechanism of nanofiller diffusion in bottlebrush polymers.
Collapse
Affiliation(s)
- Jiajun Qu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.,State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Qionghai Chen
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.,State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Wanhui Huang
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.,State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Liqun Zhang
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.,State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Jun Liu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.,State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| |
Collapse
|
7
|
Chen Y, Yan R, Zhao N. Passive and active tracer dynamics in polymer solutions with isotropic-to-nematic phase transition. Phys Chem Chem Phys 2022; 24:7415-7429. [PMID: 35266498 DOI: 10.1039/d2cp00323f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Macromolecular crowding plays a crucial role in determining the dynamics in a living cell. We adopt Langevin dynamics simulations to investigate the anomalous diffusion dynamics of passive and active particles in a solution of polymer chains with tunable stiffness. The solution's anisotropic feature is modulated by changing both the polymer stiffness and volume fraction, where isotropic-to-nematic phase transition is involved. Our results demonstrate the significant impact of polymer flexibility on the dynamics of both passive and active probes. The distinct diffusion mechanism for an active particle is clarified by the interplay between polymer stiffness, crowdedness and activity. Polymer stiffness leads to a global inhibition effect on passive particle diffusion. The diffusion coefficient exhibits an intriguing non-monotonic variation at increasing polymer stiffness, which is due to the fact that the alignment of polymer chains is beneficial for diffusion along the nematic direction but unfavorable for that in the direction perpendicular to it. In sharp contrast, polymer stiffness plays a dominant role in facilitating active particle diffusion. Self-propulsion of the particle can utilize stiffness-induced elastic interactions more efficiently, which promotes its mobility in both directions. Meanwhile, an active particle might have a stronger ability to take advantage of the polymer alignment, contributing substantially enhanced diffusivity. In addition, the diffusion coefficient of an active particle is subject to a tendency of degeneration against varying volume fraction. This counter-intuitive behavior is due to the contrasting factors that increasing crowdedness induces a lower particle speed but a longer persistent motion time.
Collapse
Affiliation(s)
- Ying Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Ran Yan
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Nanrong Zhao
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| |
Collapse
|
8
|
Reisjalali M, Burgos-Mármol JJ, Manurung R, Troisi A. Local structuring of diketopyrrolopyrrole (DPP)-based oligomers from molecular dynamics simulations. Phys Chem Chem Phys 2021; 23:19693-19707. [PMID: 34525153 DOI: 10.1039/d1cp03257g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The microscopic structure of high mobility semiconducting polymers is known to be essential for their performance but it cannot be easily deduced from the available experimental data. A series of short oligomers of diketopyrrolopyrrole (DPP)-based materials that display high charge mobility are studied by molecular dynamics simulations to understand their local structuring at an atomic level. Different analyses are proposed to compare the ability of different oligomers to form large aggregates and their driving force. The simulations show that the tendency for this class of materials to form aggregates is driven by the interaction between DPP fragments, but this is modulated by the other conjugated fragments of the materials which affect the rigidity of the polymer and, ultimately, the size of the aggregates that are formed. The main structural features and the electronic structure of the oligomers are fairly similar above the glass transition temperature and at room temperature.
Collapse
Affiliation(s)
- Maryam Reisjalali
- Department of Chemistry, University of Liverpool, Crown Place, Liverpool, L69 7ZD, UK.
| | | | - Rex Manurung
- Department of Chemistry, University of Liverpool, Crown Place, Liverpool, L69 7ZD, UK.
| | - Alessandro Troisi
- Department of Chemistry, University of Liverpool, Crown Place, Liverpool, L69 7ZD, UK.
| |
Collapse
|
9
|
Tonti L, García Daza FA, Patti A. Diffusion of globular macromolecules in liquid crystals of colloidal cuboids. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116640] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
10
|
Rheological mechanism of polymer nanocomposites filled with spherical nanoparticles: Insight from molecular dynamics simulation. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
11
|
Huang JH, Sun DD, Lu RX. Glass transition and dynamics of semiflexible polymer brushes. Phys Chem Chem Phys 2021; 23:13895-13904. [PMID: 34132280 DOI: 10.1039/d1cp00089f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The glass transition and dynamics of densely grafted semiflexible polymer brushes are studied by molecular dynamics simulation. The glass transition temperature (Tg) increases with the polymer rigidity. The local glass transition temperature (Tg,local) is estimated from the temperature-dependent dynamics of individual segments including the lateral position fluctuation and lateral mean square displacement. Different from the flexible polymer brush, Tg,local of semiflexible polymer brushes is roughly independent of the segment height. Our simulation reveals that the glass transition is in synchronism with an abrupt change of the chain conformation in semiflexible polymer brushes. When the temperature drops to near Tg, the semiflexible polymer chains elongate, tilt, and become more ordered. Moreover, enhanced segmental dynamics is observed at temperatures just above Tg for the semiflexible polymer brushes.
Collapse
Affiliation(s)
- Jian-Hua Huang
- Department of Chemistry, Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | | | | |
Collapse
|
12
|
Burgos-Mármol JJ, Patti A. Molecular Dynamics of Janus Nanodimers Dispersed in Lamellar Phases of a Block Copolymer. Polymers (Basel) 2021; 13:1524. [PMID: 34065148 PMCID: PMC8126030 DOI: 10.3390/polym13091524] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/02/2021] [Accepted: 05/03/2021] [Indexed: 12/29/2022] Open
Abstract
We investigate structural and dynamical properties of Janus nanodimers (NDs) dispersed in lamellar phases of a diblock copolymer. By performing molecular dynamics simulations, we show that an accurate tuning of the interactions between NDs and copolymer blocks can lead to a close control of NDs' space distribution and orientation. In particular, NDs are preferentially found within the lamellae if enthalpy-driven forces offset their entropic counterpart. By contrast, when enthalpy-driven forces are not significant, the distribution of NDs, preferentially observed within the inter-lamellar spacing, is mostly driven by excluded-volume effects. Not only does the degree of affinity between host and guest species drive the NDs' distribution in the polymer matrix, but it also determines their space orientation. In turn, these key structural properties influence the long-time dynamics and the ability of NDs to diffuse through the polymer matrix.
Collapse
Affiliation(s)
- J. Javier Burgos-Mármol
- Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Crown St., Liverpool L69 7ZB, UK;
| | - Alessandro Patti
- Department of Chemical Engineering and Analytical Science, The University of Manchester, The Mill. Sackville Street, Manchester M13 9PL, UK
| |
Collapse
|
13
|
Zhang B, Li J, Hu J, Liu L. Theory of polymer diffusion in polymer-nanoparticle mixtures: effect of nanoparticle concentration and polymer length. SOFT MATTER 2021; 17:4632-4642. [PMID: 33949610 DOI: 10.1039/d1sm00226k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The dynamics of polymer-nanoparticle (NP) mixtures, which involves multiple scales and system-specific variables, has posed a long-standing challenge on its theoretical description. In this paper, we construct a microscopic theory for polymer diffusion in mixtures based on a combination of the generalized Langevin equation, mode-coupling approach, and polymer physics ideas. The parameter-free theory has an explicit expression and remains tractable on a pair correlation level with system-specific equilibrium structures as input. Taking a minimal polymer-NP mixture as an example, our theory correctly captures the dependence of polymer diffusion on NP concentration and average interparticle distance. Importantly, the polymer diffusion exhibits a power law decay as the polymer length increases at dense NPs and/or a long chain, which marks the emergence of entanglement-like motion. The work provides a first-principles theoretical foundation to investigate dynamic problems in diverse polymer nanocomposites.
Collapse
Affiliation(s)
- Bokai Zhang
- Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Jian Li
- Department of Physics and Electronic Engineering, Heze University, Heze 274015, China
| | - Juanmei Hu
- Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Lei Liu
- Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| |
Collapse
|
14
|
Chen S, Olson E, Jiang S, Yong X. Nanoparticle assembly modulated by polymer chain conformation in composite materials. NANOSCALE 2020; 12:14560-14572. [PMID: 32613987 DOI: 10.1039/d0nr01740j] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Mixing nanoparticles into a strategically selected polymer matrix yields nanocomposites with well-controlled microstructures and unique properties and functions. The modulation of nanoparticle assembly by polymer chain conformation can play a dominant role in determining nanocomposite structures, yet such a physical mechanism remains largely unexplored. We hypothesize that highly ordered microdomains of rigid linear polymers provide a template for nanoparticle assembly into open fractal structures. We conducted mesoscopic computer simulations and physical experiments to elucidate how polymer chain conformation regulates the dynamic evolution of nanoparticle structures during the drying processing of polymer nanocomposite films. The evaporation of polymer-nanoparticle mixtures with varying chain stiffnesses was simulated using dissipative particle dynamics. The formation of distinguished nanoparticle assemblies as a result of matrix selection was further corroborated by probing nanoparticle aggregation in different polymer nanocomposite coatings. The results show that polymer conformation not only influences the dispersion states of individual particles (dispersed vs. aggregated), but also modulates the morphologies of large-scale assembly (globular vs. fractal). The emergence of nematically ordered polymer clusters when the chain rigidity is increased creates local solvent-rich "voids" that promote anisotropic particle aggregates, which then percolate into open fractal structures upon solvent evaporation. The nanoparticle dynamics also exhibits an intriguing non-monotonic behavior attributed to the transitions between the coupling and decoupling with polymer dynamics. The nanoparticle assembly morphologies obtained in simulations match well with the electron microscopy images taken in physical experiments.
Collapse
Affiliation(s)
- Shensheng Chen
- Department of Mechanical Engineering, Binghamton University, Binghamton, New York 13902, USA.
| | | | | | | |
Collapse
|
15
|
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]
|
16
|
Miwatani R, Takahashi KZ, Arai N. Performance of Coarse Graining in Estimating Polymer Properties: Comparison with the Atomistic Model. Polymers (Basel) 2020; 12:polym12020382. [PMID: 32046337 PMCID: PMC7077424 DOI: 10.3390/polym12020382] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/20/2020] [Accepted: 01/26/2020] [Indexed: 01/23/2023] Open
Abstract
Combining atomistic and coarse-grained (CG) models is a promising approach for quantitative prediction of polymer properties. However, the gaps between the length and time scales of atomistic and CG models still need to be bridged. Here, the scale gaps of the atomistic model of polyethylene melts, the bead–spring Kremer–Grest model, and dissipative particle dynamics with the slip-spring model were investigated. A single set of spatial and temporal scaling factors was determined between the atomistic model and each CG model. The results of the CG models were rescaled using the set of scaling factors and compared with those of the atomistic model. For each polymer property, a threshold value indicating the onset of static or dynamic universality of polymers was obtained. The scaling factors also revealed the computational efficiency of each CG model with respect to the atomistic model. The performance of the CG models of polymers was systematically evaluated in terms of both the accuracy and computational efficiency.
Collapse
Affiliation(s)
- Ryota Miwatani
- Department of Mechanical Engineering, Kindai University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8522, Japan;
| | - Kazuaki Z. Takahashi
- Research Center for Computational Design of Advanced Functional Materials, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
- Correspondence: ; Tel.: +81-29-861-2972; Fax: +81-29-861-5375
| | - Noriyoshi Arai
- Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522, Japan;
| |
Collapse
|
17
|
Zhou X, Guo F, Li K, He L, Zhang L. Entropy-induced Separation of Binary Semiflexible Ring Polymer Mixtures in Spherical Confinement. Polymers (Basel) 2019; 11:E1992. [PMID: 31810347 PMCID: PMC6960585 DOI: 10.3390/polym11121992] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 11/24/2019] [Accepted: 11/27/2019] [Indexed: 11/25/2022] Open
Abstract
Coarse-grained molecular dynamics simulations are used to investigate the conformations of binary semiflexible ring polymers (SRPs) of two different lengths confined in a hard sphere. Segregated structures of SRPs in binary mixtures are strongly dependent upon the number density of system (ρ), the bending energy of long SRPs (Kb, long), and the chain length ratio of long to short SRPs (α). With a low ρ or a weak Kb, long at a small ratio α, long SRPs are immersed randomly in the matrix of short SRPs. As ρ and bending energy of long SRPs (Kb, long) are increased up to a certain value for a large ratio α, a nearly complete segregation between long and short SRPs is observed, which can be further characterized by the ratio of tangential and radial components of long SRPs velocity. These explicit segregated structures of the two components in spherical confinement are induced by a delicate competition between the entropic excluded volume (depletion) effects and bending contributions.
Collapse
Affiliation(s)
- Xiaolin Zhou
- Department of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China; (X.Z.); (F.G.); (K.L.)
| | - Fuchen Guo
- Department of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China; (X.Z.); (F.G.); (K.L.)
| | - Ke Li
- Department of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China; (X.Z.); (F.G.); (K.L.)
| | - Linli He
- Department of Physics, Wenzhou University, Wenzhou 325035, Zhejiang, China
| | - Linxi Zhang
- Department of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China; (X.Z.); (F.G.); (K.L.)
| |
Collapse
|
18
|
Peng Y, Zhang H, Huang XW, Huang JH, Luo MB. Monte Carlo simulation on the dynamics of a semi-flexible polymer in the presence of nanoparticles. Phys Chem Chem Phys 2018; 20:26333-26343. [PMID: 30303200 DOI: 10.1039/c8cp05136d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of a semi-flexible polymer chain in the presence of periodically distributed nanoparticles is simulated by using off-lattice Monte Carlo simulations. For repulsive or weak attractive nanoparticles, the dynamics are slowed down monotonically by increasing the chain stiffness kθ or decreasing the inter-particle distance d. For strong attractive nanoparticles, however, the dynamics show nonmonotonic behaviors with kθ and d. An interesting result is that a stiff polymer may move faster than a flexible one. The underlying mechanism is that the nanoparticle's attraction is weakened by the chain stiffness. The nonmonotonic behavior of the polymer's dynamics with kθ is explained by the competition between the weakening effect of the chain stiffness on the nanoparticle's attraction and the intrinsic effect of chain stiffness which reduces the dynamics of the polymer. In addition, the nonmonotonic behavior of the polymer's dynamics with d is explained by the competition between the nanoparticle-exchange motion of the polymer dominated at small d and the desorption-and-adsorption motion at large d. The excluded volume effect of the nanoparticles plays a more important role for stiffer polymers as the attraction of the nanoparticles is weakened by the chain stiffness.
Collapse
Affiliation(s)
- Yi Peng
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Huan Zhang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Xiao-Wei Huang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Jian-Hua Huang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | - Meng-Bo Luo
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| |
Collapse
|
19
|
Volgin I, Larin S, Lyulin A, Lyulin S. Coarse-grained molecular-dynamics simulations of nanoparticle diffusion in polymer nanocomposites. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.04.058] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
20
|
Wan H, Shen J, Gao N, Liu J, Gao Y, Zhang L. Tailoring the mechanical properties by molecular integration of flexible and stiff polymer networks. SOFT MATTER 2018; 14:2379-2390. [PMID: 29503989 DOI: 10.1039/c7sm02282d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Designing a multiple-network structure at the molecular level to tailor the mechanical properties of polymeric materials is of great scientific and technological importance. Through the coarse-grained molecular dynamics simulation, we successfully construct an interpenetrating polymer network (IPN) composed of a flexible polymer network and a stiff polymer network. First, we find that there is an optimal chain stiffness for a single network (SN) to achieve the best stress-strain behavior. Then we turn to study the mechanical behaviors of IPNs. The result shows that the stress-strain behaviors of the IPNs appreciably exceed the sum of that of the corresponding single flexible and stiff network, which highlights the advantage of the IPN structure. By systematically varying the stiffness of the stiff polymer network of the IPNs, optimal stiffness also exists to achieve the best performance. We attribute this to a much larger contribution of the non-bonded interaction energy. Last, the effect of the component concentration ratio is probed. With the increase of the concentration of the flexible network, the stress-strain behavior of the IPNs is gradually enhanced, while an optimized concentration (around 60% molar ration) of the stiff network occurs, which could result from the dominant role of the enthalpy rather than the entropy. In general, our work is expected to provide some guidelines to better tailor the mechanical properties of the IPNs made of a flexible network and a stiff network, by manipulating the stiffness of the stiff polymer network and the component concentration ratio.
Collapse
Affiliation(s)
- Haixiao Wan
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, People's Republic of China.
| | - Jianxiang Shen
- Department of Polymer Science and Engineering, Jiaxing University, Jiaxing 314001, P. R. China
| | - Naishen Gao
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, People's Republic of China.
| | - Jun Liu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, People's Republic of China. and Beijing Engineering Research Center of Advanced Elastomers, Beijing University of Chemical Technology, People's Republic of China and Engineering Research Center of Elastomer Materials on Energy Conservation and Resources, Beijing University of Chemical Technology, People's Republic of China and Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 100029 Beijing, People's Republic of China
| | - Yangyang Gao
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, People's Republic of China.
| | - Liqun Zhang
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, People's Republic of China. and Beijing Engineering Research Center of Advanced Elastomers, Beijing University of Chemical Technology, People's Republic of China and Engineering Research Center of Elastomer Materials on Energy Conservation and Resources, Beijing University of Chemical Technology, People's Republic of China and Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 100029 Beijing, People's Republic of China and State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 100029 Beijing, People's Republic of China
| |
Collapse
|
21
|
Li SJ, Qian HJ, Lu ZY. Translational and rotational dynamics of an ultra-thin nanorod probe particle in linear polymer melts. Phys Chem Chem Phys 2018; 20:20996-21007. [DOI: 10.1039/c8cp03653e] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Translational and rotational dynamics of a single rigid ultra-thin nanorod probe particle in linear polymer melts are investigated using coarse-grained molecular dynamics (CG-MD) simulations.
Collapse
Affiliation(s)
- Shu-Jia Li
- State Key Laboratory of Supramolecular Structure and Materials
- Laboratory of Theoretical and Computational Chemistry
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Institute of Theoretical Chemistry
- Jilin University
| | - Hu-Jun Qian
- State Key Laboratory of Supramolecular Structure and Materials
- Laboratory of Theoretical and Computational Chemistry
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Institute of Theoretical Chemistry
- Jilin University
| | - Zhong-Yuan Lu
- State Key Laboratory of Supramolecular Structure and Materials
- Laboratory of Theoretical and Computational Chemistry
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Institute of Theoretical Chemistry
- Jilin University
| |
Collapse
|