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Title: Cavitation and radicals drive the sonochemical synthesis of functional polymer spheres

Abstract

Sonochemical synthesis can lead to a dramatic increase in the kinetics of formation of polymer spheres (templates for carbon spheres) compared to the modified Stöber silica method applied to produce analogous polymer spheres. Reactive molecular dynamics simulations of the sonochemical process indicate a significantly enhanced rate of polymer sphere formation starting from resorcinol and formaldehyde precursors. The associated chemical reaction kinetics enhancement due to sonication is postulated to arise from the localized lowering of atomic densities, localized heating, and generation of radicals due to cavitation collapse in aqueous systems. This dramatic increase in reaction rates translates into enhanced nucleation and growth of the polymer spheres. The results are of broad significance to understanding mechanisms of sonication induced synthesis as well as technologies utilizing polymers spheres.

Authors:
; ;  [1]; ;  [2];  [3]
  1. Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
  2. World Premier International Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044 (Japan)
  3. School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)
Publication Date:
OSTI Identifier:
22594436
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARBON; CAVITATION; CHEMICAL REACTION KINETICS; CHEMICAL REACTIONS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DENSITY; FORMALDEHYDE; HEATING; MOLECULAR DYNAMICS METHOD; NUCLEATION; POLYMERS; PRECURSOR; RADICALS; RESORCINOL; SILICA; SPHERES; SYNTHESIS

Citation Formats

Narayanan, Badri, E-mail: bnarayanan@anl.gov, Deshmukh, Sanket A., Sankaranarayanan, Subramanian K. R. S., E-mail: ssankaranarayanan@anl.gov, Shrestha, Lok Kumar, Ariga, Katsuhiko, and Pol, Vilas G.. Cavitation and radicals drive the sonochemical synthesis of functional polymer spheres. United States: N. p., 2016. Web. doi:10.1063/1.4959885.
Narayanan, Badri, E-mail: bnarayanan@anl.gov, Deshmukh, Sanket A., Sankaranarayanan, Subramanian K. R. S., E-mail: ssankaranarayanan@anl.gov, Shrestha, Lok Kumar, Ariga, Katsuhiko, & Pol, Vilas G.. Cavitation and radicals drive the sonochemical synthesis of functional polymer spheres. United States. doi:10.1063/1.4959885.
Narayanan, Badri, E-mail: bnarayanan@anl.gov, Deshmukh, Sanket A., Sankaranarayanan, Subramanian K. R. S., E-mail: ssankaranarayanan@anl.gov, Shrestha, Lok Kumar, Ariga, Katsuhiko, and Pol, Vilas G.. 2016. "Cavitation and radicals drive the sonochemical synthesis of functional polymer spheres". United States. doi:10.1063/1.4959885.
@article{osti_22594436,
title = {Cavitation and radicals drive the sonochemical synthesis of functional polymer spheres},
author = {Narayanan, Badri, E-mail: bnarayanan@anl.gov and Deshmukh, Sanket A. and Sankaranarayanan, Subramanian K. R. S., E-mail: ssankaranarayanan@anl.gov and Shrestha, Lok Kumar and Ariga, Katsuhiko and Pol, Vilas G.},
abstractNote = {Sonochemical synthesis can lead to a dramatic increase in the kinetics of formation of polymer spheres (templates for carbon spheres) compared to the modified Stöber silica method applied to produce analogous polymer spheres. Reactive molecular dynamics simulations of the sonochemical process indicate a significantly enhanced rate of polymer sphere formation starting from resorcinol and formaldehyde precursors. The associated chemical reaction kinetics enhancement due to sonication is postulated to arise from the localized lowering of atomic densities, localized heating, and generation of radicals due to cavitation collapse in aqueous systems. This dramatic increase in reaction rates translates into enhanced nucleation and growth of the polymer spheres. The results are of broad significance to understanding mechanisms of sonication induced synthesis as well as technologies utilizing polymers spheres.},
doi = {10.1063/1.4959885},
journal = {Applied Physics Letters},
number = 4,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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