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Title: Particle dynamics in polymer-metal nanocomposite thin films on nanometer-length scales.

Abstract

X-ray photon correlation spectroscopy was used in conjunction with resonance-enhanced grazing-incidence small-angle x-ray scattering to probe slow particle dynamics and kinetics in gold/polystyrene nanocomposite thin films. Such enhanced coherent scattering enables, for the first time, measurement of the particle dynamics at wave vectors up to {approx}1 nm-1 (or a few nanometers spatially) in a disordered system, well in the regime where entanglement, confinement, and particle interaction dominate the dynamics and kinetics. Measurements of the intermediate structure factor f(q,t) indicate that the particle dynamics differ from Stokes-Einstein Brownian motion and are explained in terms of viscoelastic effects and interparticle interactions.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
914970
Report Number(s):
ANL/XSD/JA-58753
Journal ID: ISSN 0031-9007; PRLTAO; TRN: US0804860
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Rev. Lett.; Journal Volume: 98; Journal Issue: May 4, 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COHERENT SCATTERING; CONFINEMENT; INTERMEDIATE STRUCTURE; KINETICS; PARTICLE INTERACTIONS; PHOTONS; PROBES; SCATTERING; SPECTROSCOPY; THIN FILMS; VECTORS

Citation Formats

Narayanan, S., Lee, D. R., Hagman, A., Li, X., Wang, J., X-Ray Science Division, and Northwestern Univ. Particle dynamics in polymer-metal nanocomposite thin films on nanometer-length scales.. United States: N. p., 2007. Web. doi:10.1103/PhysRevLett.98.185506.
Narayanan, S., Lee, D. R., Hagman, A., Li, X., Wang, J., X-Ray Science Division, & Northwestern Univ. Particle dynamics in polymer-metal nanocomposite thin films on nanometer-length scales.. United States. doi:10.1103/PhysRevLett.98.185506.
Narayanan, S., Lee, D. R., Hagman, A., Li, X., Wang, J., X-Ray Science Division, and Northwestern Univ. Fri . "Particle dynamics in polymer-metal nanocomposite thin films on nanometer-length scales.". United States. doi:10.1103/PhysRevLett.98.185506.
@article{osti_914970,
title = {Particle dynamics in polymer-metal nanocomposite thin films on nanometer-length scales.},
author = {Narayanan, S. and Lee, D. R. and Hagman, A. and Li, X. and Wang, J. and X-Ray Science Division and Northwestern Univ.},
abstractNote = {X-ray photon correlation spectroscopy was used in conjunction with resonance-enhanced grazing-incidence small-angle x-ray scattering to probe slow particle dynamics and kinetics in gold/polystyrene nanocomposite thin films. Such enhanced coherent scattering enables, for the first time, measurement of the particle dynamics at wave vectors up to {approx}1 nm-1 (or a few nanometers spatially) in a disordered system, well in the regime where entanglement, confinement, and particle interaction dominate the dynamics and kinetics. Measurements of the intermediate structure factor f(q,t) indicate that the particle dynamics differ from Stokes-Einstein Brownian motion and are explained in terms of viscoelastic effects and interparticle interactions.},
doi = {10.1103/PhysRevLett.98.185506},
journal = {Phys. Rev. Lett.},
number = May 4, 2007,
volume = 98,
place = {United States},
year = {Fri May 04 00:00:00 EDT 2007},
month = {Fri May 04 00:00:00 EDT 2007}
}
  • X-ray photon correlation spectroscopy was used in conjunction with resonance-enhanced grazing-incidence small-angle x-ray scattering to probe slow particle dynamics and kinetics in gold/polystyrene nanocomposite thin films. Such enhanced coherent scattering enables, for the first time, measurement of the particle dynamics at wave vectors up to {approx}1 nm{sup -1} (or a few nanometers spatially) in a disordered system, well in the regime where entanglement, confinement, and particle interaction dominate the dynamics and kinetics. Measurements of the intermediate structure factor f(q,t) indicate that the particle dynamics differ from Stokes-Einstein Brownian motion and are explained in terms of viscoelastic effects and interparticle interactions.
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  • Nanocomposite thin films were prepared with polyurethane as a matrix and organically modified clay as a filler. The interfacial interaction between the exfoliated clay nanoplatelets and the polymeric chains has been investigated by using Atomic Force Microscopy (AFM). The nanoclay platelets show a preferential association with the hard domains of polyurethane matrix on the surface of the thin films. The pendant hydroxyl group on the nanoplatelets attract the isocyanate of the polyisocyanate and a urethane group is formed. This leads to the 'clouding' and 'entwining' of the nanoplatelets by the hard segmental chains. This is the first visual evidence ofmore » nanomaterial filler and polymer matrix interaction and it could open up a spectrum of novel property achievements in nanocomposite thin films. Also the understanding of this interaction can lead to more controlled architecture of nanocomposites.« less