The mechanisms of copolymerization of three anionic polymerizable surfactants (surfmers)a methacrylic ester, a crotonic ester, and a maleic esterin the emulsion terpolymerization of styrene/butyl acrylate/acrylic acid (S/BA/AA) were investigated. In order to clarify the contribution of each polymerization loci in the process, polymerization in the aqueous phase in the absence of both micelles and monomer droplets and emulsion polymerizations with different solids contents (30, 50, and 55 wt %) and different particle sizes were carried out. It was found that the methacrylic ester surfmer appeared to be extremely reactive and caused premature coagulation. The crotonic ester surfmer reacted only to a small extent and was not incorporated well enough into the polymer latex. The maleic diester surfmer appeared to have intermediate conversions varying between 50% and 95%. It was clearly shown that the degree of conversion of this surfmer depended on the particle diameter, with the conversion decreasing significantly at diameters higher than 100 nm. Although the maleate surfmer was the best of the three surfmers, its optimum use is not straightforward because high conversion of the surfmer led to the burying of a significant fraction of the maleate inside the polymer particles. Suggestions for a more advantageous incorporation are made.

Film formation of three different latices was studied using atomic force microscopy. The latices were made from a mixture of butyl acrylate, styrene, and acrylic acid using either a polymerizable or an unreactive anionic surfactant as an emulsifier. Sodium 11-crotonoyloxyundecan-1-ylsulfate and sodium 3-(sulfopropyl)tetradecylmaleate were used as a reactive surfactant and the unreactive surfactant was sodium dodecylsulfate (SDS). The conventional surfactant was found to migrate to the surface of the latex film to a much greater extent than did the reactive surfactants; however, also, the latter were incompletely anchored to the particle. The maleate surfactant was bound to a higher degree than was the crotonate, a finding which is in line with the relative reactivities of the two surfactants.

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Several polymerizable surfactants (surfmers) have been used in the semicontinuous emulsion copolymerization of styrene, butyl acrylate, and acrylic acid. Three of the (anionic) surfmers (sodium 11-crotonoyl undecan-1-yl sulfate, sodium 11-methacryloyl undecan-1-sulfate, and sodium sulfopropyl tetradecyl maleate) were prepared in house with purities between 53 and 82%. Physicochemical properties such as the critical micelle concentration, the adsorption isotherm, and the specific adsorption area were determined. The surfmers were then used with constant addition profiles in semicontinuous reactions, and the instantaneous conversions of the main monomers determined. The particle size, amount of coagulum, surface tension, and stability against electrolyte solutions of the latices were evaluated. Films were cast of some of the latices, and the visual appearance and water adsorption were assessed.

In this article the results obtained with latexes prepared by emulsion polymerization with a conventional surfactant and a polymerizable surfactant (surfmer) are presented. For this study, well‐defined styrene‐butylacrylate latexes with a conventional nonreactive surfactant (sodium dodecyl sulfate) and a maleate diester surfmer, of which films can be easily cast, were used. The latex with the surfmer was prepared following a surfmer addition strategy to maximize the amount of surfmer bound to the particle surface, and not buried in the particle interior. The latex properties in terms of mechanical stability, film‐water absorption, and film‐surfactant exudation were assessed and compared. The mechanical stability and water‐absorption properties of the latex prepared with surfmer were better than those of the latex with sodium dodecyl sulfate. Additionally, by using a surfmer the surfactant migration to the film‐substrate and film‐air interfaces can be inhibited. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2994–3000, 2002