Excluded volume effects in compressed polymer brushes: A density functional theory
Abstract
A classical density functional theory (DFT) is applied to investigate the behavior of compressed polymer brushes composed of hardsphere chains. The excluded volume interactions among the chain segments are explicitly treated. Two compression systems are used to study the behavior of brushwall and brushbrush interactions. For the brushbrush systems, an obvious interpenetration zone has been observed. The extent of the interpenetration depends strongly on the grafting density. Furthermore, the repulsive force between the brush and wall or between the two brushes has been obtained as a function of the compression distance. Compared to the prediction of the analytic selfconsistent field theory, such force increases more rapidly in the brushwall compression with high polymer grafting densities or at higher compressions. In the brushbrush compression system, the interpenetration between the two compressed brushes creates a “softer” interaction. The influence of hardsphere solvents on the behavior of compressed brushes is also discussed.
 Authors:
 The State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433 (China)
 Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1 (Canada)
 Publication Date:
 OSTI Identifier:
 22415582
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; COMPARATIVE EVALUATIONS; COMPRESSION; DENSITY FUNCTIONAL METHOD; GRAFTS; POLYMERS; SELFCONSISTENT FIELD; SOLVENTS; SPHERES
Citation Formats
Chen, Cangyi, Tang, Ping, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn, Qiu, Feng, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn, and Shi, AnChang. Excluded volume effects in compressed polymer brushes: A density functional theory. United States: N. p., 2015.
Web. doi:10.1063/1.4916133.
Chen, Cangyi, Tang, Ping, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn, Qiu, Feng, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn, & Shi, AnChang. Excluded volume effects in compressed polymer brushes: A density functional theory. United States. doi:10.1063/1.4916133.
Chen, Cangyi, Tang, Ping, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn, Qiu, Feng, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn, and Shi, AnChang. 2015.
"Excluded volume effects in compressed polymer brushes: A density functional theory". United States.
doi:10.1063/1.4916133.
@article{osti_22415582,
title = {Excluded volume effects in compressed polymer brushes: A density functional theory},
author = {Chen, Cangyi and Tang, Ping, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn and Qiu, Feng, Email: pingtang@fudan.edu.cn, Email: fengqiu@fudan.edu.cn and Shi, AnChang},
abstractNote = {A classical density functional theory (DFT) is applied to investigate the behavior of compressed polymer brushes composed of hardsphere chains. The excluded volume interactions among the chain segments are explicitly treated. Two compression systems are used to study the behavior of brushwall and brushbrush interactions. For the brushbrush systems, an obvious interpenetration zone has been observed. The extent of the interpenetration depends strongly on the grafting density. Furthermore, the repulsive force between the brush and wall or between the two brushes has been obtained as a function of the compression distance. Compared to the prediction of the analytic selfconsistent field theory, such force increases more rapidly in the brushwall compression with high polymer grafting densities or at higher compressions. In the brushbrush compression system, the interpenetration between the two compressed brushes creates a “softer” interaction. The influence of hardsphere solvents on the behavior of compressed brushes is also discussed.},
doi = {10.1063/1.4916133},
journal = {Journal of Chemical Physics},
number = 12,
volume = 142,
place = {United States},
year = 2015,
month = 3
}

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