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Title: Dense Cluster Formation during Aggregation and Gelation of Attractive Slippery Nanoemulsion Droplets

Abstract

Using time-resolved small angle neutron scattering, we have measured the wave-number-dependent structure factor S(q) of monodisperse nanoemulsions that aggregate and gel after we suddenly turn on a strong, short-range, slippery attraction between the droplets. At high q, peaks in S(q) appear as dense clusters of droplets form, and S(q) increases strongly toward low q, as these dense clusters become locked into a rigid gel network, despite the fluidity of the films between the droplets. The long-time high-q structure of nanoemulsion gels formed by slippery diffusion-limited cluster aggregation is universal in shape and remarkably independent of the droplet volume fraction, {phi}.

Authors:
; ; ; ;  [1];  [2]
  1. Department of Chemistry and Biochemistry, Department of Physics and Astronomy, California NanoSystems Institute, University of California-Los Angeles, Los Angeles, California 90095 (United States)
  2. Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
Publication Date:
OSTI Identifier:
20775022
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevLett.96.015501; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AGGLOMERATION; DIFFUSION; DROPLETS; GELATION; GELS; MICROEMULSIONS; NANOSTRUCTURES; NEUTRON DIFFRACTION; SMALL ANGLE SCATTERING; STRUCTURE FACTORS; TIME RESOLUTION

Citation Formats

Wilking, J.N., Graves, S.M., Chang, C.B., Meleson, K., Mason, T.G., and Lin, M.Y. Dense Cluster Formation during Aggregation and Gelation of Attractive Slippery Nanoemulsion Droplets. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.015501.
Wilking, J.N., Graves, S.M., Chang, C.B., Meleson, K., Mason, T.G., & Lin, M.Y. Dense Cluster Formation during Aggregation and Gelation of Attractive Slippery Nanoemulsion Droplets. United States. doi:10.1103/PhysRevLett.96.015501.
Wilking, J.N., Graves, S.M., Chang, C.B., Meleson, K., Mason, T.G., and Lin, M.Y. Fri . "Dense Cluster Formation during Aggregation and Gelation of Attractive Slippery Nanoemulsion Droplets". United States. doi:10.1103/PhysRevLett.96.015501.
@article{osti_20775022,
title = {Dense Cluster Formation during Aggregation and Gelation of Attractive Slippery Nanoemulsion Droplets},
author = {Wilking, J.N. and Graves, S.M. and Chang, C.B. and Meleson, K. and Mason, T.G. and Lin, M.Y.},
abstractNote = {Using time-resolved small angle neutron scattering, we have measured the wave-number-dependent structure factor S(q) of monodisperse nanoemulsions that aggregate and gel after we suddenly turn on a strong, short-range, slippery attraction between the droplets. At high q, peaks in S(q) appear as dense clusters of droplets form, and S(q) increases strongly toward low q, as these dense clusters become locked into a rigid gel network, despite the fluidity of the films between the droplets. The long-time high-q structure of nanoemulsion gels formed by slippery diffusion-limited cluster aggregation is universal in shape and remarkably independent of the droplet volume fraction, {phi}.},
doi = {10.1103/PhysRevLett.96.015501},
journal = {Physical Review Letters},
number = 1,
volume = 96,
place = {United States},
year = {Fri Jan 13 00:00:00 EST 2006},
month = {Fri Jan 13 00:00:00 EST 2006}
}
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