1
|
Mesoscale Modeling of Agglomeration of Molecular Bottlebrushes: Focus on Conformations and Clustering Criteria. Polymers (Basel) 2022; 14:polym14122339. [PMID: 35745920 PMCID: PMC9227207 DOI: 10.3390/polym14122339] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 02/04/2023] Open
Abstract
Using dissipative particle dynamics, we characterize dynamics of aggregation of molecular bottlebrushes in solvents of various qualities by tracking the number of clusters, the size of the largest cluster, and an average aggregation number. We focus on a low volume fraction of bottlebrushes in a range of solvents and probe three different cutoff criteria to identify bottlebrushes belonging to the same cluster. We demonstrate that the cutoff criteria which depend on both the coordination number and the length of the side chain allows one to correlate the agglomeration status with the structural characteristics of bottlebrushes in solvents of various qualities. We characterize conformational changes of the bottlebrush within the agglomerates with respect to those of an isolated bottlebrush in the same solvents. The characterization of bottlebrush conformations within the agglomerates is an important step in understanding the relationship between the bottlebrush architecture and material properties. An analysis of three distinct cutoff criteria to identify bottlebrushes belonging to the same cluster introduces a framework to identify both short-lived transient and long-lived agglomerates; the same approach could be further extended to characterize agglomerates of various macromolecules with complex architectures beyond the specific bottlebrush architecture considered herein.
Collapse
|
2
|
Kol R, De Somer T, D'hooge DR, Knappich F, Ragaert K, Achilias DS, De Meester S. State-Of-The-Art Quantification of Polymer Solution Viscosity for Plastic Waste Recycling. CHEMSUSCHEM 2021; 14:4071-4102. [PMID: 34324273 PMCID: PMC8519067 DOI: 10.1002/cssc.202100876] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 07/14/2021] [Indexed: 05/17/2023]
Abstract
Solvent-based recycling is a promising approach for closed-loop recovery of plastic-containing waste. It avoids the energy cost to depolymerize the plastic but still allows to clean the polymer of contaminants and additives. However, viscosity plays an important role in handling the polymer solutions at high concentrations and in the cleaning steps. This Review addresses the viscosity behavior of polymer solutions, available data, and (mostly algebraic) models developed. The non-Newtonian viscosity models, such as the Carreau and Yasuda-Cohen-Armstrong models, pragmatically describe the viscosity of polymer solutions at different concentrations and shear rate ranges. This Review also describes how viscosity influences filtration and centrifugation processes, which are crucial steps in the cleaning of the polymer and includes a polystyrene/styrene case study.
Collapse
Affiliation(s)
- Rita Kol
- Laboratory for Circular Process Engineering (LCPE)Department of Green Chemistry and TechnologyGhent UniversityGraaf Karel De Goedelaan 58500KortrijkBelgium
- Laboratory of Polymer Chemistry and TechnologyDepartment of ChemistryAristotle University of Thessaloniki54124ThessalonikiGreece
| | - Tobias De Somer
- Laboratory for Circular Process Engineering (LCPE)Department of Green Chemistry and TechnologyGhent UniversityGraaf Karel De Goedelaan 58500KortrijkBelgium
| | - Dagmar R. D'hooge
- Laboratory for Chemical Technology (LCT) and Centre for Textiles Science and Engineering (CTSE)Department of MaterialsTextiles and Chemical EngineeringFaculty of Engineering and ArchitectureGhent UniversityTechnologiepark 125 and 70a9052ZwijnaardeBelgium
| | - Fabian Knappich
- Process Development for Polymer RecyclingFraunhofer Institute for Process Engineering and Packaging IVVGiggenhauser Straße 3585354FreisingGermany
- Technical University of MunichTUM School of Life Sciences WeihenstephanAlte Akademie 885354FreisingGermany
| | - Kim Ragaert
- Center for Polymer & Material Technologies (CPMT)Department of MaterialsTextiles and Chemical EngineeringFaculty of Engineering & ArchitectureGhent UniversityTechnologiepark 130B-9052ZwijnaardeBelgium
| | - Dimitris S. Achilias
- Laboratory of Polymer Chemistry and TechnologyDepartment of ChemistryAristotle University of Thessaloniki54124ThessalonikiGreece
| | - Steven De Meester
- Laboratory for Circular Process Engineering (LCPE)Department of Green Chemistry and TechnologyGhent UniversityGraaf Karel De Goedelaan 58500KortrijkBelgium
| |
Collapse
|
3
|
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
|
4
|
Xu S, Lou Y, He P, Wang X, Wang J. Effect of solvent quality on Poiseuille flow of polymer solutions in microchannels: A dissipative particle dynamics study. J Appl Polym Sci 2019. [DOI: 10.1002/app.47345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Shaofeng Xu
- Ningbo Institute of Technology; Zhejiang University; Zhejiang China
- Department of Mechanical Engineering; Northwestern University; Evanston Illinois 60208
| | - Yinghou Lou
- Ningbo Institute of Technology; Zhejiang University; Zhejiang China
| | - Ping He
- Ningbo Institute of Technology; Zhejiang University; Zhejiang China
| | - Xiangyang Wang
- Ningbo Institute of Technology; Zhejiang University; Zhejiang China
| | - Jiugen Wang
- School of Mechanical Engineering; Zhejiang University; Zhejiang China
| |
Collapse
|
5
|
Vanya P, Sharman J, Elliott JA. Invariance of experimental observables with respect to coarse-graining in standard and many-body dissipative particle dynamics. J Chem Phys 2019; 150:064101. [PMID: 30770006 DOI: 10.1063/1.5046851] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Dissipative particle dynamics (DPD) is a well-established mesoscale simulation method. However, there have been long-standing ambiguities regarding the dependence of its (purely repulsive) force field parameter on temperature as well as the variation of the resulting experimental observables, such as diffusivity or surface tension, with coarse-graining (CG) degree. Here, we rederive the temperature dependence of DPD interaction parameter and revisit the role of the CG degree in standard DPD simulations. Consequently, we derive a scaling of the input variables that renders the system properties invariant with respect to CG degree and illustrate the versatility of the method by computing the surface tensions of binary solvent mixtures. We then extend this procedure to many-body dissipative particle dynamics and, by computing surface tensions of the same mixtures at a range of CG degrees, demonstrate that this newer method, which has not been widely applied so far, is also capable of simulating complex fluids of practical interest.
Collapse
Affiliation(s)
- Peter Vanya
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - Jonathan Sharman
- Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading RG4 9NH, United Kingdom
| | - James A Elliott
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| |
Collapse
|
6
|
Morphology evolution of Janus dumbbell nanoparticles in seeded emulsion polymerization. J Colloid Interface Sci 2019; 543:34-42. [PMID: 30776668 DOI: 10.1016/j.jcis.2019.01.109] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 01/22/2019] [Accepted: 01/24/2019] [Indexed: 12/11/2022]
Abstract
Emulsion polymerization is a versatile approach to produce different polymeric nanoparticle morphologies, which can be useful in a variety of applications. However, the detailed mechanism of the morphology formation is not entirely clear. We study the kinetics of nanoparticle morphology evolution during a seeded emulsion polymerization using both experimental and computational tools. Lightly crosslinked polystyrene seeds were first synthesized using dispersion polymerization. Then the seed particles were swollen in tert-butyl acrylate and styrene monomers, and subsequently polymerized into nanoparticles of dumbbell and multilobe morphologies. It was discovered that both the seed and final particle morphology were affected by the methanol concentration during the seed synthesis. Systematically adjusting the methanol amount will not only yield spherical seed particles of different size, but also dumbbell particles even without the second monomer polymerization. In addition to methanol concentration, morphology can be controlled by crosslinking density. The kinetics studies revealed an interesting transition from multilobe to dumbbell geometries during the secondary polymerization. Based on the results, a nucleation-growth model has been proposed to describe the morphology evolution and verification was offered by computer simulation. The key discovery is that nanoparticle morphology can be kinetically controlled by diffusion of the protrusions on the seed particles. The condition of seed synthesis and crosslinking density will drastically change the seed and final nanoparticle morphology.
Collapse
|
7
|
Hagita K, Murashima T, Iwaoka N. Thinning Approximation for Calculating Two-Dimensional Scattering Patterns in Dissipative Particle Dynamics Simulations under Shear Flow. Polymers (Basel) 2018; 10:E1224. [PMID: 30961149 PMCID: PMC6290630 DOI: 10.3390/polym10111224] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 10/26/2018] [Accepted: 11/01/2018] [Indexed: 11/16/2022] Open
Abstract
Modifications to improve thinning approximation (TA) were considered in order to calculate two-dimensional scattering patterns (2DSPs) for dissipative particle dynamics (DPD) simulations of polymer melts under a shear flow. We proposed multipoint TA and adaptive TA because the bond lengths in DPD chains vary widely when compared to those in Kremer⁻Grest (KG) chains, and the effectiveness of these two types of TA for the two major DPD parameter sets were investigated. In this paper, we report our findings on the original DPD model with soft bonds and that with rigid bonds. Based on the behavior of the 2DSPs and the distribution of orientations of the bond vectors, two spot patterns originating from the oriented chain correlations were observed when distinct distributions of the highly oriented bond vectors in the shear direction were obtained. For multipoint TA, we concluded that at least two additional midpoints ( n mid ≥ 2 ) are required to clearly observe the two spot patterns. For adaptive TA, a dividing distance of l ATA ≤ 0.4 is sufficient for clear observation, which is consistent with the requirement of n mid ≥ 2 for multipoint TA.
Collapse
Affiliation(s)
- Katsumi Hagita
- Department of Applied Physics, National Defense Academy, Yokosuka 239-8686, Japan.
| | | | - Nobuyuki Iwaoka
- Department of Creative Engineering, Tsuruoka College, National Institute of Technology, Yamagata 997-8511, Japan.
| |
Collapse
|
8
|
Iwaoka N, Hagita K, Takano H. Multipoint segmental repulsive potential for entangled polymer simulations with dissipative particle dynamics. J Chem Phys 2018; 149:114901. [PMID: 30243288 DOI: 10.1063/1.5046755] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A model is developed for simulating entangled polymers by dissipative particle dynamics (DPD) using the segmental repulsive potential (SRP). In contrast to previous SRP models that define a single-point interaction on each bond, the proposed SRP model applies a dynamically adjustable multipoint on the bond. Previous SRP models could not reproduce the equilibrium properties of Groot and Warren's original DPD model [R. D. Groot and P. B. Warren, J. Chem. Phys. 107, 4423 (1997)] because the introduction of a single SRP induces a large excluded volume, whereas, the proposed multipoint SRP (MP-SRP) introduces a cylindrical effective excluded bond volume. We demonstrate that our MP-SRP model exhibits equilibrium properties similar to those of the original DPD polymers. The MP-SRP model parameters are determined by monitoring the number of topology violations, thermodynamic properties, and the polymer internal structure. We examine two typical DPD polymers with different bond-length distributions; one of them was used in the modified SRP model by Sirk et al. [J. Chem. Phys. 136, 134903 (2012)], whereas the other was used in the original DPD model. We demonstrate that for both polymers, the proposed MP-SRP model captures the entangled behaviors of a polymer melt naturally, by calculating the slowest relaxation time of a chain in the melt and the shear relaxation modulus. The results indicate that the proposed MP-SRP model can be applied to a variety of DPD polymers.
Collapse
Affiliation(s)
- Nobuyuki Iwaoka
- Department of Creative Engineering, Tsuruoka College, National Institute of Technology, 104 Sawada, Inooka, Tsuruoka, Yamagata 997-8511, Japan
| | - Katsumi Hagita
- Department of Applied Physics, National Defense Academy, 1-10-20, Hashirimizu, Yokosuka 239-8686, Japan
| | - Hiroshi Takano
- Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| |
Collapse
|
9
|
Chen S, Yong X. Dissipative particle dynamics modeling of hydrogel swelling by osmotic ensemble method. J Chem Phys 2018; 149:094904. [DOI: 10.1063/1.5045100] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Shensheng Chen
- Department of Mechanical Engineering, Binghamton University, The State University of New York, 4400 Vestal Parkway East, Binghamton, New York 13902, USA
| | - Xin Yong
- Department of Mechanical Engineering, Binghamton University, The State University of New York, 4400 Vestal Parkway East, Binghamton, New York 13902, USA
- Institute for Materials Research, Binghamton University, The State University of New York, 4400 Vestal Parkway East, Binghamton, New York 13902, USA
| |
Collapse
|
10
|
Weng YH, Tsao HK, Sheng YJ. Self-healing and dewetting dynamics of a polymer nanofilm on a smooth substrate: strategies for dewetting suppression. Phys Chem Chem Phys 2018; 20:20459-20467. [PMID: 30043813 DOI: 10.1039/c8cp03215g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The self-healing and dewetting dynamics of a polymer nanofilm on a smooth, partial wetting surface are explored by many-body dissipative particle dynamics. Three types of dewetting phenomena are identified, (i) spinodal decomposition, (ii) nucleation and growth, and (iii) metastable self-healing. The outcome depends on the surface wettability (θY), the polymer film thickness (h0), and the radius of the dry hole (R0). The phase diagram of the dewetting mechanism as a function of θY and h0 is obtained for a specified R0. As the surface wettability decreases (increasing θY), the critical film thickness associated with the nucleation/self-healing crossover (hc) grows so that the metastability of the film can be retained by the self-healing process. In addition to θY and R0, hc depends on the polymer length (N) as well. It is found that a longer polymer requires a thicker nanofilm to avoid dewetting by nucleation. Two strategies for dewetting suppression are proposed. The metastability of a film of polymers with a large molecular weight can be promoted either by the addition of short polymers or by employing compact polymers such as star polymers. In the latter approach, the increment of the arm number enhances the nanofilm stability.
Collapse
Affiliation(s)
- Yu-Hsuan Weng
- Department of Chemical Engineering, National Taiwan University, Taipei, 10617, Taiwan.
| | | | | |
Collapse
|
11
|
Zhao J, Chen S, Phan-Thien N. Rheology of polymers in many-body dissipative particle dynamics simulations: Schmidt number effect. MOLECULAR SIMULATION 2018. [DOI: 10.1080/08927022.2018.1453139] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Jiayi Zhao
- School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai, China
- Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore
| | - Shuo Chen
- School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai, China
| | - Nhan Phan-Thien
- Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore
| |
Collapse
|
12
|
Sretenovic S, Stojković B, Dogsa I, Kostanjšek R, Poberaj I, Stopar D. An early mechanical coupling of planktonic bacteria in dilute suspensions. Nat Commun 2017; 8:213. [PMID: 28790301 PMCID: PMC5548916 DOI: 10.1038/s41467-017-00295-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 06/19/2017] [Indexed: 11/13/2022] Open
Abstract
It is generally accepted that planktonic bacteria in dilute suspensions are not mechanically coupled and do not show correlated motion. The mechanical coupling of cells is a trait that develops upon transition into a biofilm, a microbial community of self-aggregated bacterial cells. Here we employ optical tweezers to show that bacteria in dilute suspensions are mechanically coupled and show long-range correlated motion. The strength of the coupling increases with the growth of liquid bacterial culture. The matrix responsible for the mechanical coupling is composed of cell debris and extracellular polymer material. The fragile network connecting cells behaves as viscoelastic liquid of entangled extracellular polymers. Our findings point to physical connections between bacteria in dilute bacterial suspensions that may provide a mechanistic framework for understanding of biofilm formation, osmotic flow of nutrients, diffusion of signal molecules in quorum sensing, or different efficacy of antibiotic treatments at low and high bacterial densities.Planktonic bacteria are untethered to surfaces or to each other, and thus are expected to move independently when at low cell densities. Here Sretenovic et al. show, using optical tweezers, that bacteria in dilute suspensions are mechanically coupled and show long-range correlated motion.
Collapse
Affiliation(s)
- Simon Sretenovic
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia
| | - Biljana Stojković
- Medical Faculty, Institute of Biophysics, University of Ljubljana, Vrazov trg 2, Ljubljana, 1000, Slovenia
| | - Iztok Dogsa
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia
| | - Rok Kostanjšek
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia
| | - Igor Poberaj
- Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, Ljubljana, 1000, Slovenia
- Aresis Ltd., Ulica Franca Mlakarja 1a, Ljubljana, 1000, Slovenia
| | - David Stopar
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia.
| |
Collapse
|
13
|
Qin S, Yong X. Interfacial adsorption of pH-responsive polymers and nanoparticles. SOFT MATTER 2017; 13:5137-5149. [PMID: 28657632 DOI: 10.1039/c7sm00637c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Using dissipative particle dynamics (DPD), we model the interfacial adsorption of pH-responsive polyelectrolytes and polyelectrolyte-grafted nanoparticles (PNPs) at a planar water-oil interface. The electrostatic interactions in the presence of the dielectric discontinuity across the interface are modeled by exploiting the Groot method, which uses an iterative method to solve the Poisson equation on a uniform grid with distributed charge. We reveal the effects of the pH and salinity of the aqueous solution and the length of the polyelectrolyte on the adsorption behavior of weak polyelectrolytes. The adsorption kinetics is monitored via the trajectory of the center of mass of the polyelectrolyte in the direction normal to the interface. The residence time at the interface and the pair correlation function between the polyelectrolyte and the oil are measured to quantitatively characterize the adsorption. Similar to the weak polyelectrolytes, the influences of pH, salinity and grafted chain length on the adsorption of an individual PNP are explored. Our results show that by grafting polyelectrolytes, the interfacial behavior of the nanoparticles can be tuned by changing the pH and salinity of the solution, which is dictated by the contact angle, the pair correlation function between the particles and the oil, the desorption energy, and the particle morphology at the interface. We also observe that the electrostatic-driven variations in the interfacial activity and morphology of the PNPs are not sensitive to the length of the grafted polyelectrolytes.
Collapse
Affiliation(s)
- Shiyi Qin
- Department of Mechanical Engineering, Binghamton University, The State University of New York, Binghamton, New York 13902, USA.
| | | |
Collapse
|