skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Multiscale Dynamics of Polymers in Particle-Rich Nanocomposites

Abstract

In this paper we report on the dynamics of entangled polymers in polymer–nanoparticle composites (PNCs) with moderate and high particle loadings. Using composites comprised of poly(ethylene glycol) (PEG)-tethered silica (SiO 2) nanoparticles and poly(methyl methacrylate) (PMMA), we show by means of small-angle X-ray scattering (SAXS) analysis that the nanoparticles are uniformly dispersed over a range of particle concentrations. From oscillatory shear rheology measurements, we find that the time–temperature superposition (TTS) principle holds for these SiO 2-PEG/PMMA PNCs up to a particle concentration Φ G ≈ 11% where the materials begin to exhibit soft glassy rheological properties. At particle concentrations below Φ G, we take advantage of TTS to create dynamic maps for PNCs that span time scales ranging from fast segmental motions to slow terminal relaxation of polymer chains. These maps reveal that at low Φ and depending on the host polymer (PMMA) molecular weight ( M w), hairy nanoparticles may either speed up or slow down terminal relaxation of the host. In contrast, at high Φ, nanoparticles slow down polymer dynamics on intermediate and long time scales, irrespective of the host polymer M w. The slowdown coincides with particle concentrations at which the mean interparticle spacing lies below themore » equilibrium tube diameter of the entangled PMMA host and is thought to reflect the onset of confinement dynamics of polymer chains in PNCs. Studies of PNCs in the confinement regime reveal important analogies between glassy attributes of 3D-confined polymer chains in nanocomposites with those of polymer thin films supported on attractive substrates.« less

Authors:
 [1];  [1];  [1];  [1]
  1. Cornell Univ., Ithaca, NY (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Science Foundation (NSF)
OSTI Identifier:
1327063
Grant/Contract Number:  
CBET-1512297; AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Macromolecules
Additional Journal Information:
Journal Volume: 49; Journal Issue: 14; Journal ID: ISSN 0024-9297
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Polymer particles; Nanoparticles; Nanocomposites; Organic compounds; Polymers

Citation Formats

Mangal, Rahul, Wen, Yu Ho, Choudhury, Snehashis, and Archer, Lynden A. Multiscale Dynamics of Polymers in Particle-Rich Nanocomposites. United States: N. p., 2016. Web. doi:10.1021/acs.macromol.6b00496.
Mangal, Rahul, Wen, Yu Ho, Choudhury, Snehashis, & Archer, Lynden A. Multiscale Dynamics of Polymers in Particle-Rich Nanocomposites. United States. doi:10.1021/acs.macromol.6b00496.
Mangal, Rahul, Wen, Yu Ho, Choudhury, Snehashis, and Archer, Lynden A. Thu . "Multiscale Dynamics of Polymers in Particle-Rich Nanocomposites". United States. doi:10.1021/acs.macromol.6b00496. https://www.osti.gov/servlets/purl/1327063.
@article{osti_1327063,
title = {Multiscale Dynamics of Polymers in Particle-Rich Nanocomposites},
author = {Mangal, Rahul and Wen, Yu Ho and Choudhury, Snehashis and Archer, Lynden A.},
abstractNote = {In this paper we report on the dynamics of entangled polymers in polymer–nanoparticle composites (PNCs) with moderate and high particle loadings. Using composites comprised of poly(ethylene glycol) (PEG)-tethered silica (SiO2) nanoparticles and poly(methyl methacrylate) (PMMA), we show by means of small-angle X-ray scattering (SAXS) analysis that the nanoparticles are uniformly dispersed over a range of particle concentrations. From oscillatory shear rheology measurements, we find that the time–temperature superposition (TTS) principle holds for these SiO2-PEG/PMMA PNCs up to a particle concentration ΦG ≈ 11% where the materials begin to exhibit soft glassy rheological properties. At particle concentrations below ΦG, we take advantage of TTS to create dynamic maps for PNCs that span time scales ranging from fast segmental motions to slow terminal relaxation of polymer chains. These maps reveal that at low Φ and depending on the host polymer (PMMA) molecular weight (Mw), hairy nanoparticles may either speed up or slow down terminal relaxation of the host. In contrast, at high Φ, nanoparticles slow down polymer dynamics on intermediate and long time scales, irrespective of the host polymer Mw. The slowdown coincides with particle concentrations at which the mean interparticle spacing lies below the equilibrium tube diameter of the entangled PMMA host and is thought to reflect the onset of confinement dynamics of polymer chains in PNCs. Studies of PNCs in the confinement regime reveal important analogies between glassy attributes of 3D-confined polymer chains in nanocomposites with those of polymer thin films supported on attractive substrates.},
doi = {10.1021/acs.macromol.6b00496},
journal = {Macromolecules},
issn = {0024-9297},
number = 14,
volume = 49,
place = {United States},
year = {2016},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 8 works
Citation information provided by
Web of Science

Save / Share: