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Title: Experimental Evidence for a New Parameter to Control the Glass Transition of Confined Polymers

Abstract

Polymer nanocomposites can be used to study confinement effects on the polymer glass transition temperature (T{sub g}) in a controlled manner by varying interparticle spacing. Using gold nanoparticles in polymethylmethacrylate, we show how the polymer T{sub g} can be tuned by variation of the nanoparticle-polymer interface width ({sigma}), keeping interparticle spacing fixed. We report the first experimental observation of a crossover in the sign of T{sub g} deviation for confined polymers by variation of {sigma} and propose a model to explain the dependence of crossover width on the spatial extent of cooperatively rearranging regions.

Authors:
;  [1]
  1. Department of Physics, Indian Institute of Science, Bangalore 560 012 (India)
Publication Date:
OSTI Identifier:
20951259
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 16; Other Information: DOI: 10.1103/PhysRevLett.98.165701; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPOSITE MATERIALS; GLASS; GOLD; INTERFACES; NANOSTRUCTURES; PARTICLES; POLYMERS; TRANSITION TEMPERATURE

Citation Formats

Srivastava, S., and Basu, J. K. Experimental Evidence for a New Parameter to Control the Glass Transition of Confined Polymers. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.165701.
Srivastava, S., & Basu, J. K. Experimental Evidence for a New Parameter to Control the Glass Transition of Confined Polymers. United States. doi:10.1103/PHYSREVLETT.98.165701.
Srivastava, S., and Basu, J. K. Fri . "Experimental Evidence for a New Parameter to Control the Glass Transition of Confined Polymers". United States. doi:10.1103/PHYSREVLETT.98.165701.
@article{osti_20951259,
title = {Experimental Evidence for a New Parameter to Control the Glass Transition of Confined Polymers},
author = {Srivastava, S. and Basu, J. K.},
abstractNote = {Polymer nanocomposites can be used to study confinement effects on the polymer glass transition temperature (T{sub g}) in a controlled manner by varying interparticle spacing. Using gold nanoparticles in polymethylmethacrylate, we show how the polymer T{sub g} can be tuned by variation of the nanoparticle-polymer interface width ({sigma}), keeping interparticle spacing fixed. We report the first experimental observation of a crossover in the sign of T{sub g} deviation for confined polymers by variation of {sigma} and propose a model to explain the dependence of crossover width on the spatial extent of cooperatively rearranging regions.},
doi = {10.1103/PHYSREVLETT.98.165701},
journal = {Physical Review Letters},
number = 16,
volume = 98,
place = {United States},
year = {Fri Apr 20 00:00:00 EDT 2007},
month = {Fri Apr 20 00:00:00 EDT 2007}
}
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