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Title: Influence of the bound polymer layer on nanoparticle diffusion in polymer melts

Abstract

We measure the center-of-mass diffusion of silica nanoparticles (NPs) in entangled poly(2-vinylpyridine) (P2VP) melts using Rutherford backscattering spectrometry. While these NPs are well within the size regime where enhanced, nonhydrodynamic NP transport is theoretically predicted and has been observed experimentally (2R NP/d tube ≈ 3, where 2R NP is the NP diameter and d tube is the tube diameter), we find that the diffusion of these NPs in P2VP is in fact well-described by the hydrodynamic Stokes–Einstein relation. The effective NP diameter 2R eff is significantly larger than 2R NP and strongly dependent on P2VP molecular weight, consistent with the presence of a bound polymer layer on the NP surface with thickness h eff ≈ 1.1R g. Our results show that the bound polymer layer significantly augments the NP hydrodynamic size in polymer melts with attractive polymer–NP interactions and effectively transitions the mechanism of NP diffusion from the nonhydrodynamic to hydrodynamic regime, particularly at high molecular weights where NP transport is expected to be notably enhanced. Lastly, these results provide the first experimental demonstration that hydrodynamic NP transport in polymer melts requires particles of size ≳5d tube, consistent with recent theoretical predictions.

Authors:
 [1];  [2];  [1];  [1];  [3];  [4];  [1]
  1. Univ. of Pennsylvania, Philadelphia, PA (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Univ. of Sheffield, Sheffield (United Kingdom)
  4. Univ. of Illinois, Urbana, IL (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1326520
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Macro Letters
Additional Journal Information:
Journal Volume: 5; Journal ID: ISSN 2161-1653
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Griffin, Philip J., Bocharova, Vera, Middleton, L. Robert, Composto, Russell J., Clarke, Nigel, Schweizer, Kenneth S., and Winey, Karen I.. Influence of the bound polymer layer on nanoparticle diffusion in polymer melts. United States: N. p., 2016. Web. doi:10.1021/acsmacrolett.6b00649.
Griffin, Philip J., Bocharova, Vera, Middleton, L. Robert, Composto, Russell J., Clarke, Nigel, Schweizer, Kenneth S., & Winey, Karen I.. Influence of the bound polymer layer on nanoparticle diffusion in polymer melts. United States. doi:10.1021/acsmacrolett.6b00649.
Griffin, Philip J., Bocharova, Vera, Middleton, L. Robert, Composto, Russell J., Clarke, Nigel, Schweizer, Kenneth S., and Winey, Karen I.. 2016. "Influence of the bound polymer layer on nanoparticle diffusion in polymer melts". United States. doi:10.1021/acsmacrolett.6b00649. https://www.osti.gov/servlets/purl/1326520.
@article{osti_1326520,
title = {Influence of the bound polymer layer on nanoparticle diffusion in polymer melts},
author = {Griffin, Philip J. and Bocharova, Vera and Middleton, L. Robert and Composto, Russell J. and Clarke, Nigel and Schweizer, Kenneth S. and Winey, Karen I.},
abstractNote = {We measure the center-of-mass diffusion of silica nanoparticles (NPs) in entangled poly(2-vinylpyridine) (P2VP) melts using Rutherford backscattering spectrometry. While these NPs are well within the size regime where enhanced, nonhydrodynamic NP transport is theoretically predicted and has been observed experimentally (2RNP/dtube ≈ 3, where 2RNP is the NP diameter and dtube is the tube diameter), we find that the diffusion of these NPs in P2VP is in fact well-described by the hydrodynamic Stokes–Einstein relation. The effective NP diameter 2Reff is significantly larger than 2RNP and strongly dependent on P2VP molecular weight, consistent with the presence of a bound polymer layer on the NP surface with thickness heff ≈ 1.1Rg. Our results show that the bound polymer layer significantly augments the NP hydrodynamic size in polymer melts with attractive polymer–NP interactions and effectively transitions the mechanism of NP diffusion from the nonhydrodynamic to hydrodynamic regime, particularly at high molecular weights where NP transport is expected to be notably enhanced. Lastly, these results provide the first experimental demonstration that hydrodynamic NP transport in polymer melts requires particles of size ≳5dtube, consistent with recent theoretical predictions.},
doi = {10.1021/acsmacrolett.6b00649},
journal = {ACS Macro Letters},
number = ,
volume = 5,
place = {United States},
year = 2016,
month = 9
}

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Cited by: 6works
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