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Title: Structure and Dynamics of Ionic Block Copolymer Melts: Computational Study

Abstract

Structure and dynamics of melts of copolymers with an ABCBA topology, where C is an ionizable block, have been studied by fully atomistic molecular dynamics (MD) simulations. Introducing an ionizable block for functionality adds a significant element to the coupled set of interactions that determine the structure and dynamics of the macromolecule. The polymer consists of a randomly sulfonated polystyrene C block tethered to a flexible poly(ethylene-r-propylene) bridge B and end-capped with poly(tert-butylstyrene) A. The chemical structure and topology of these polymers constitute a model for incorporation of ionic blocks within a framework that provides tactility and mechanical stability. Here in this paper we resolve the structure and dynamics of a structured polymer on the nanoscale constrained by ionic clusters. We find that the melts form intertwined networks of the A and C blocks independent of the degree of sulfonation of the C block with no long-range order. The cluster cohesiveness and morphology affect both macroscopic translational motion and segmental dynamics of all the blocks.

Authors:
 [1];  [2];  [3]; ORCiD logo [4]
  1. Clemson Univ., SC (United States). Dept. of Chemistry
  2. Clemson Univ., SC (United States). Dept. of Chemistry; Washington Univ., St. Louis, MO (United States). Dept. of Mechanical Engineering and Materials Science
  3. Clemson Univ., SC (United States). Dept. of Chemistry; Clemson Univ., SC (United States). Dept. of Physics
  4. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1398785
Report Number(s):
SAND-2017-10263J
Journal ID: ISSN 0024-9297; 657207
Grant/Contract Number:
AC04-94AL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Macromolecules
Additional Journal Information:
Journal Volume: 50; Journal Issue: 18; Journal ID: ISSN 0024-9297
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Aryal, Dipak, Agrawal, Anupriya, Perahia, Dvora, and Grest, Gary S. Structure and Dynamics of Ionic Block Copolymer Melts: Computational Study. United States: N. p., 2017. Web. doi:10.1021/acs.macromol.7b00724.
Aryal, Dipak, Agrawal, Anupriya, Perahia, Dvora, & Grest, Gary S. Structure and Dynamics of Ionic Block Copolymer Melts: Computational Study. United States. doi:10.1021/acs.macromol.7b00724.
Aryal, Dipak, Agrawal, Anupriya, Perahia, Dvora, and Grest, Gary S. 2017. "Structure and Dynamics of Ionic Block Copolymer Melts: Computational Study". United States. doi:10.1021/acs.macromol.7b00724.
@article{osti_1398785,
title = {Structure and Dynamics of Ionic Block Copolymer Melts: Computational Study},
author = {Aryal, Dipak and Agrawal, Anupriya and Perahia, Dvora and Grest, Gary S.},
abstractNote = {Structure and dynamics of melts of copolymers with an ABCBA topology, where C is an ionizable block, have been studied by fully atomistic molecular dynamics (MD) simulations. Introducing an ionizable block for functionality adds a significant element to the coupled set of interactions that determine the structure and dynamics of the macromolecule. The polymer consists of a randomly sulfonated polystyrene C block tethered to a flexible poly(ethylene-r-propylene) bridge B and end-capped with poly(tert-butylstyrene) A. The chemical structure and topology of these polymers constitute a model for incorporation of ionic blocks within a framework that provides tactility and mechanical stability. Here in this paper we resolve the structure and dynamics of a structured polymer on the nanoscale constrained by ionic clusters. We find that the melts form intertwined networks of the A and C blocks independent of the degree of sulfonation of the C block with no long-range order. The cluster cohesiveness and morphology affect both macroscopic translational motion and segmental dynamics of all the blocks.},
doi = {10.1021/acs.macromol.7b00724},
journal = {Macromolecules},
number = 18,
volume = 50,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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