Seeded emulsion polymerizations of styrene. The fate of exited free radicals

Whang, B. C. Y., Napper, D. H., Ballard, M. J., Gilbert, R. G. and Lichti, G. (1982) Seeded emulsion polymerizations of styrene. The fate of exited free radicals. Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 78 1117-1126. doi:10.1039/f19827801117


Author Whang, B. C. Y.
Napper, D. H.
Ballard, M. J.
Gilbert, R. G.
Lichti, G.
Title Seeded emulsion polymerizations of styrene. The fate of exited free radicals
Journal name Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases   Check publisher's open access policy
ISSN 0300-9599
Publication date 1982-01-01
Sub-type Article (original research)
DOI 10.1039/f19827801117
Open Access Status Not Open Access
Volume 78
Start page 1117
End page 1126
Total pages 10
Place of publication Cambridge, United Kingdom
Publisher Royal Society of Chemistry
Language eng
Abstract The kinetics of the seeded emulsion polymerization of styrene at different particle number concentrations and different initiator concentrations have been studied. The results were analysed using a theoretical treatment that incorporates the possibilities of both the re-entry of exited free radicals into the latex particles and the cross-termination in the aqueous phase of exited free radicals by free radicals generated through initiator decomposition. The results exclude the possibility of complete re-entry of exited free radicals into the latex particles for the initiator concentrations studied. They strongly support the occurrence of significant cross-termination in the aqueous phase of the exited free radicals with free radicals generated by initiator decomposition. This is in accordance with the known rapidity of cross-termination reactions compared with the corresponding self-termination reactions. It was also shown that the rate of entry of free radicals into each latex particle increases with decreasing particle number at constant initiator concentration. The radical capture efficiency was, however, relatively insensitive to the particle number concentration. The overall polymerization rate was found to be a complex function of the number concentration of latex particles; this is because this overall rate is itself a complicated function of the rate coefficients for entry, exit, etc. each of which may be individually a simple function of number concentration. Such behaviour reflects significant deviations from Smith-Ewart case 2 kinetics that occur in these systems, rather than deviations from the general Smith-Ewart kinetic scheme.
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: Centre for Nutrition and Food Sciences Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 46 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 40 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 08 Mar 2011, 01:59:38 EST