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Title: Unraveling the Agglomeration Mechanism in Charged Block Copolymer and Surfactant Complexes

Abstract

Here, we report a molecular dynamics simulation investigation of self-assembly and complex formation of charged-neutral double hydrophilic and hydrophobic-hydrophilic block copolymers (BCP) with oppositely charged surfactants. Furthermore, the structure of the surfactant micelles and the BCP aggregation on the micelle surface is systematically studied for five different BCP volume fractions that also mimics a reduction of the surfactant concentration. The local electrostatic interactions between the oppositely charged species encourage the formation of core-shell structures between the surfactant micelles where the surfactants form the cores and the charged blocks of the BCP form the corona. The emergent morphologies of these aggregates are contingent upon the nature of the BCP neutral blocks. The hydrophilic neutral blocks agglomerate with the micelles as hairy colloidal structures while the hydrophobic neutrals agglomerate in lamellar structures with the surfactant micelles. The distribution of counterion charges along the simulation box show a close-to-normal density distribution for the hydrophilic neutral blocks and a binodal distribution for hydrophobic neutral blocks. No specific surfactant concentration dependent scaling relation is observed as opposed to the simpler case of homo-polyelectrolytes.

Authors:
 [1];  [2]; ORCiD logo [3]; ORCiD logo [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Neutron Data Analysis and Visualization
  2. Univ. of California, Santa Barbara, CA (United States). Dept. of Materials Science
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences and Computer Science and Mathematics Division
Publication Date:
Research Org.:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF); Joint Institute for Computational Sciences (JICS)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1346670
Grant/Contract Number:
AC05-00OR22725; AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Macromolecules
Additional Journal Information:
Journal Volume: 50; Journal Issue: 3; Journal ID: ISSN 0024-9297
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Borreguero, Jose M., Pincus, Philip A., Sumpter, Bobby G., and Goswami, Monojoy. Unraveling the Agglomeration Mechanism in Charged Block Copolymer and Surfactant Complexes. United States: N. p., 2017. Web. doi:10.1021/acs.macromol.6b02319.
Borreguero, Jose M., Pincus, Philip A., Sumpter, Bobby G., & Goswami, Monojoy. Unraveling the Agglomeration Mechanism in Charged Block Copolymer and Surfactant Complexes. United States. doi:10.1021/acs.macromol.6b02319.
Borreguero, Jose M., Pincus, Philip A., Sumpter, Bobby G., and Goswami, Monojoy. Fri . "Unraveling the Agglomeration Mechanism in Charged Block Copolymer and Surfactant Complexes". United States. doi:10.1021/acs.macromol.6b02319. https://www.osti.gov/servlets/purl/1346670.
@article{osti_1346670,
title = {Unraveling the Agglomeration Mechanism in Charged Block Copolymer and Surfactant Complexes},
author = {Borreguero, Jose M. and Pincus, Philip A. and Sumpter, Bobby G. and Goswami, Monojoy},
abstractNote = {Here, we report a molecular dynamics simulation investigation of self-assembly and complex formation of charged-neutral double hydrophilic and hydrophobic-hydrophilic block copolymers (BCP) with oppositely charged surfactants. Furthermore, the structure of the surfactant micelles and the BCP aggregation on the micelle surface is systematically studied for five different BCP volume fractions that also mimics a reduction of the surfactant concentration. The local electrostatic interactions between the oppositely charged species encourage the formation of core-shell structures between the surfactant micelles where the surfactants form the cores and the charged blocks of the BCP form the corona. The emergent morphologies of these aggregates are contingent upon the nature of the BCP neutral blocks. The hydrophilic neutral blocks agglomerate with the micelles as hairy colloidal structures while the hydrophobic neutrals agglomerate in lamellar structures with the surfactant micelles. The distribution of counterion charges along the simulation box show a close-to-normal density distribution for the hydrophilic neutral blocks and a binodal distribution for hydrophobic neutral blocks. No specific surfactant concentration dependent scaling relation is observed as opposed to the simpler case of homo-polyelectrolytes.},
doi = {10.1021/acs.macromol.6b02319},
journal = {Macromolecules},
number = 3,
volume = 50,
place = {United States},
year = {Fri Jan 27 00:00:00 EST 2017},
month = {Fri Jan 27 00:00:00 EST 2017}
}

Journal Article:
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