A simple many-body Hamiltonian for polymer-colloid mixtures: simulations and mean-field theory
(2012) In Soft Matter 8(7). p.2121-2130- Abstract
- We investigate depletion interactions between inert hard colloids in the presence of ideal polymers, with a focus on the case where the polymer radius of gyration (R-g) is equal to the radius of the colloids (R-c). We first establish structure and fluid-fluid phase equilibria of this model system as accurately as possible. To achieve this, we replace the ideal polymers by "effective spheres'', using the approach of Bolhuis and Louis [P. Bolhuis and A. A. Louis, Macromolecules, 2002, 35, 1860.] With this approach, we have been able to simulate (approximate) fluid-fluid phase diagrams in dispersions containing relatively long chains, up to 2401-mers (R-g = R-c = 20 bond lengths). We devote some effort to illustrate many-body effects, and... (More)
- We investigate depletion interactions between inert hard colloids in the presence of ideal polymers, with a focus on the case where the polymer radius of gyration (R-g) is equal to the radius of the colloids (R-c). We first establish structure and fluid-fluid phase equilibria of this model system as accurately as possible. To achieve this, we replace the ideal polymers by "effective spheres'', using the approach of Bolhuis and Louis [P. Bolhuis and A. A. Louis, Macromolecules, 2002, 35, 1860.] With this approach, we have been able to simulate (approximate) fluid-fluid phase diagrams in dispersions containing relatively long chains, up to 2401-mers (R-g = R-c = 20 bond lengths). We devote some effort to illustrate many-body effects, and demonstrate that, at least relatively close to the respective critical point, there is a much stronger tendency to form clusters in the low density phase when many-body interactions are taken into account. This is primarily due to the repulsive contributions from higher-order interactions in the liquid, enforcing a high critical polymer chemical potential. At such a high chemical potential, there is a significant tendency to form small clusters in the gas phase. The results of these "effective sphere'' simulations are compared with predictions by a polymer+colloid many-body theory that was recently proposed by us. Our results suggest that this theory, even at the mean-field level is surprisingly accurate. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2425498
- author
- Forsman, Jan LU and Woodward, Clifford E.
- organization
- publishing date
- 2012
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Soft Matter
- volume
- 8
- issue
- 7
- pages
- 2121 - 2130
- publisher
- Royal Society of Chemistry
- external identifiers
-
- wos:000299477300007
- scopus:84856718071
- ISSN
- 1744-6848
- DOI
- 10.1039/c2sm06737d
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039)
- id
- 72f8c6f1-d8da-48e9-9d27-07b992e801f2 (old id 2425498)
- date added to LUP
- 2016-04-01 13:38:37
- date last changed
- 2023-01-03 23:57:02
@article{72f8c6f1-d8da-48e9-9d27-07b992e801f2,
abstract = {{We investigate depletion interactions between inert hard colloids in the presence of ideal polymers, with a focus on the case where the polymer radius of gyration (R-g) is equal to the radius of the colloids (R-c). We first establish structure and fluid-fluid phase equilibria of this model system as accurately as possible. To achieve this, we replace the ideal polymers by "effective spheres'', using the approach of Bolhuis and Louis [P. Bolhuis and A. A. Louis, Macromolecules, 2002, 35, 1860.] With this approach, we have been able to simulate (approximate) fluid-fluid phase diagrams in dispersions containing relatively long chains, up to 2401-mers (R-g = R-c = 20 bond lengths). We devote some effort to illustrate many-body effects, and demonstrate that, at least relatively close to the respective critical point, there is a much stronger tendency to form clusters in the low density phase when many-body interactions are taken into account. This is primarily due to the repulsive contributions from higher-order interactions in the liquid, enforcing a high critical polymer chemical potential. At such a high chemical potential, there is a significant tendency to form small clusters in the gas phase. The results of these "effective sphere'' simulations are compared with predictions by a polymer+colloid many-body theory that was recently proposed by us. Our results suggest that this theory, even at the mean-field level is surprisingly accurate.}},
author = {{Forsman, Jan and Woodward, Clifford E.}},
issn = {{1744-6848}},
language = {{eng}},
number = {{7}},
pages = {{2121--2130}},
publisher = {{Royal Society of Chemistry}},
series = {{Soft Matter}},
title = {{A simple many-body Hamiltonian for polymer-colloid mixtures: simulations and mean-field theory}},
url = {{http://dx.doi.org/10.1039/c2sm06737d}},
doi = {{10.1039/c2sm06737d}},
volume = {{8}},
year = {{2012}},
}