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Title: Effect of Nanoscopic Fillers on Deweting Dynamics

Abstract

We synthesized C{sub 18}-functionalized gold and palladium nanoparticles with average diameter size of 10 and 3 nm, respectively, and carried out a systematic study of the effect of nanoscale metallic fillers on the dewetting dynamics of PS/PMMA bilayer substrates. Optical and atomic force microscopies were used to study the hole growth and determine the viscosity of the films as a function of PS molecular weight, particle radius, and concentration. Neutron reflectivity was used to measure the effects of the nanoparticles on the tracer diffusion coefficient. X-ray reflectivity and TEM microscopy were used to study the distribution of the particles within the film and ensure that no segregation or clustering occurred. The results indicated that the dynamics are a sensitive function of the ratio between the filler radius, R{sub particle}, and the polymer radius of gyration, R{sub g}. The data were found to collapse on a universal curve where the relative velocity of the filled system was faster than that for the unfilled system when R{sub g}/R{sub particle} > 4 and slower when R{sub g}/R{sub particle} < 4. Shear modulation force microscopy method (SMFM) measurements were performed as a function of temperature and indicated that T{sub g} was depressed by 12more » C relative to the bulk when R{sub g}/R{sub particle} > 4 and unchanged when R{sub g}/R{sub particle} < 4. The results were interpreted in terms of an increase in the local excluded volume and possible elastic distortions of the polymer matrix.« less

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
914112
Report Number(s):
BNL-78680-2007-JA
TRN: US0801548
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Macromolecules; Journal Volume: 39
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; DIFFUSION; DISTRIBUTION; FILLERS; GOLD; MICROSCOPY; MODULATION; MOLECULAR WEIGHT; NEUTRONS; PALLADIUM; POLYMERS; REFLECTIVITY; SEGREGATION; SHEAR; SUBSTRATES; VISCOSITY; national synchrotron light source

Citation Formats

Xavier,J., Sharma, S., Seo, Y., Isseroff, R., Koga, T., White, H., Ulman, A., Shin, K., Satija, S., and et al. Effect of Nanoscopic Fillers on Deweting Dynamics. United States: N. p., 2006. Web. doi:10.1021/ma050454m.
Xavier,J., Sharma, S., Seo, Y., Isseroff, R., Koga, T., White, H., Ulman, A., Shin, K., Satija, S., & et al. Effect of Nanoscopic Fillers on Deweting Dynamics. United States. doi:10.1021/ma050454m.
Xavier,J., Sharma, S., Seo, Y., Isseroff, R., Koga, T., White, H., Ulman, A., Shin, K., Satija, S., and et al. Sun . "Effect of Nanoscopic Fillers on Deweting Dynamics". United States. doi:10.1021/ma050454m.
@article{osti_914112,
title = {Effect of Nanoscopic Fillers on Deweting Dynamics},
author = {Xavier,J. and Sharma, S. and Seo, Y. and Isseroff, R. and Koga, T. and White, H. and Ulman, A. and Shin, K. and Satija, S. and et al.},
abstractNote = {We synthesized C{sub 18}-functionalized gold and palladium nanoparticles with average diameter size of 10 and 3 nm, respectively, and carried out a systematic study of the effect of nanoscale metallic fillers on the dewetting dynamics of PS/PMMA bilayer substrates. Optical and atomic force microscopies were used to study the hole growth and determine the viscosity of the films as a function of PS molecular weight, particle radius, and concentration. Neutron reflectivity was used to measure the effects of the nanoparticles on the tracer diffusion coefficient. X-ray reflectivity and TEM microscopy were used to study the distribution of the particles within the film and ensure that no segregation or clustering occurred. The results indicated that the dynamics are a sensitive function of the ratio between the filler radius, R{sub particle}, and the polymer radius of gyration, R{sub g}. The data were found to collapse on a universal curve where the relative velocity of the filled system was faster than that for the unfilled system when R{sub g}/R{sub particle} > 4 and slower when R{sub g}/R{sub particle} < 4. Shear modulation force microscopy method (SMFM) measurements were performed as a function of temperature and indicated that T{sub g} was depressed by 12 C relative to the bulk when R{sub g}/R{sub particle} > 4 and unchanged when R{sub g}/R{sub particle} < 4. The results were interpreted in terms of an increase in the local excluded volume and possible elastic distortions of the polymer matrix.},
doi = {10.1021/ma050454m},
journal = {Macromolecules},
number = ,
volume = 39,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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