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6631361 
Journal Article 
MECHANISM OF EMULSION POLYMERIZATION OF STYRENE IN SOAP-FREE SYSTEMS 
Goodall, AR; Wilkinson, MC; Hearn, J; , 
1977 
Yes 
Journal of Polymer Science. Part A, Polymer Chemistry
ISSN: 0887-624X
EISSN: 1099-0518 
JOHN WILEY & SONS INC 
NEW YORK 
15 
9 
2193-2218 
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WOS:A1977DT67000012 
In the reported experiments, the formation and growth of monodisperse polystyrene latex particles in the absence of added surfactant has been studied by sampling polymerization reactions at different times and determining the surface and bulk properties of the latex. The rate of polymerization per particle was found to be proportional to the particle radius. Gel-permeation chromatography has shown that the initial particles consist mainly of material of MW 1000 with a small amount of polymer up to MW 10**6, and the presence of this low molecular weight polymer, which in many cases can still be detected after 100% conversion, is taken as being indicative of particle formation via a micellization-type mechanism involving short-chain (MW 500) free-radical oligomers. The presence of anomalous regions within the particles has been confirmed by transmission electron microscopy, scanning electron microscopy, and gas adsorption studies. The presence of sulfate, carboxyl, and hydroxyl groups upon the latex particle surfaces has been determined by conductometric titration.