Surface forces at restricted equilibrium, in solutions containing finite or infinite semiflexible polymers
(2007) In Macromolecules 40(23). p.8396-8408- Abstract
- We use density functional theory to investigate how the presence of polymers influence the interactions between adsorbing or nonadsorbing flat surfaces, forming a slit geometry. The study is primarily made under "restricted equilibrium" conditions, i.e., below a threshold separation, the chains are allowed to equilibrate conformationally between the surfaces, but they are unable to diffuse into or out from the slit. This is believed to be a reasonable model for commonly encountered experimental situations, when the surfaces are large and adsorbing and the polymers are long. Using a recently presented density functional theory, we are able to compare predictions for chains of finite and infinite length. A major advantage of the infinite... (More)
- We use density functional theory to investigate how the presence of polymers influence the interactions between adsorbing or nonadsorbing flat surfaces, forming a slit geometry. The study is primarily made under "restricted equilibrium" conditions, i.e., below a threshold separation, the chains are allowed to equilibrate conformationally between the surfaces, but they are unable to diffuse into or out from the slit. This is believed to be a reasonable model for commonly encountered experimental situations, when the surfaces are large and adsorbing and the polymers are long. Using a recently presented density functional theory, we are able to compare predictions for chains of finite and infinite length. A major advantage of the infinite chain formulation is that it is a high resolution theory, and predictions from the finite length version will exactly approach the ones for infinite chains, when the degree of polymerization becomes large enough. Our study spans across a relatively large number of relevant system parameters, such as bulk concentration, surface adsorption strength, polymer length, and chain flexibility. The response in terms of the net surface interaction, to a change of a system parameter, is often nonmonotonic. We also make comparisons with predictions it full equilibrium, where the diffusion constraint has been relaxed. We give a specific example of how a diffusion-limited process can lead to hysteresis effects, similar to those observed in many surface force measurements. Finally, in a separate section of this work, we have included some direct experimental comparisons, demonstrating the relevance and applicability of restricted equilibrium conditions to "real world" scenarios. The computational power of the density functional approach is here highlighted, with calculations including semiflexible 20000-mers. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/971855
- author
- Forsman, Jan LU and Woodward, Clifford E.
- organization
- publishing date
- 2007
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Macromolecules
- volume
- 40
- issue
- 23
- pages
- 8396 - 8408
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000250801700040
- scopus:36349002935
- ISSN
- 0024-9297
- DOI
- 10.1021/ma071181t
- 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
- f7a7d8dd-7464-460e-be4f-decb7bb5d4fd (old id 971855)
- date added to LUP
- 2016-04-01 11:35:51
- date last changed
- 2023-01-02 20:38:22
@article{f7a7d8dd-7464-460e-be4f-decb7bb5d4fd,
abstract = {{We use density functional theory to investigate how the presence of polymers influence the interactions between adsorbing or nonadsorbing flat surfaces, forming a slit geometry. The study is primarily made under "restricted equilibrium" conditions, i.e., below a threshold separation, the chains are allowed to equilibrate conformationally between the surfaces, but they are unable to diffuse into or out from the slit. This is believed to be a reasonable model for commonly encountered experimental situations, when the surfaces are large and adsorbing and the polymers are long. Using a recently presented density functional theory, we are able to compare predictions for chains of finite and infinite length. A major advantage of the infinite chain formulation is that it is a high resolution theory, and predictions from the finite length version will exactly approach the ones for infinite chains, when the degree of polymerization becomes large enough. Our study spans across a relatively large number of relevant system parameters, such as bulk concentration, surface adsorption strength, polymer length, and chain flexibility. The response in terms of the net surface interaction, to a change of a system parameter, is often nonmonotonic. We also make comparisons with predictions it full equilibrium, where the diffusion constraint has been relaxed. We give a specific example of how a diffusion-limited process can lead to hysteresis effects, similar to those observed in many surface force measurements. Finally, in a separate section of this work, we have included some direct experimental comparisons, demonstrating the relevance and applicability of restricted equilibrium conditions to "real world" scenarios. The computational power of the density functional approach is here highlighted, with calculations including semiflexible 20000-mers.}},
author = {{Forsman, Jan and Woodward, Clifford E.}},
issn = {{0024-9297}},
language = {{eng}},
number = {{23}},
pages = {{8396--8408}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Macromolecules}},
title = {{Surface forces at restricted equilibrium, in solutions containing finite or infinite semiflexible polymers}},
url = {{http://dx.doi.org/10.1021/ma071181t}},
doi = {{10.1021/ma071181t}},
volume = {{40}},
year = {{2007}},
}