A survey is given of recent developments in emulsion polymerization regarding improved auxiliary materials, e.g. vinyl tensides and surface active initiators. Results of the emulsion polymerization of styrene are presented with 3‐(alkyloxycarbonyl‐acryloyloxy)propanesulfonates (2) as polymerizable emulsifiers and with surface active azo initiators. The results show, that the content of water soluble surface active compounds in the latexes can be reduced. Investigations of the molecular weight of the polymers show the great importance of the initiator‐emulsifier system. Azo initiators leading to higher molecular weights than persulfate. Under the same conditions the highest molecular weights were obtained with a surface active azo initiator.

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.

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Monomeric emulsifiers with different copolymerization reactivities were used as stabilizers in emulsion polymerization of styrene initiated by 2,2'azobisisobutyronitrile (AIBN). A significant change in emulsifier function was observed between equal micellar concentrations of surface-active sodium sulfopropyl alkyl maleates and the corresponding sodium sulfopropyl dodecyl fumarate. In the presence of less reactive maleates, copolymerization mainly occurs in the interface of the monomer swollen particles, while copolymerization with the fumarate in the first period of emulsion polymerization leads to polyelectrolyte formation in the water phase.

The interaction between latex particles with covalently bound ionic groups and polyelectrolytes was studied by dynamic and static light scattering. In the systems investigated two effects occurred: a coating of the latex particles with a closed-fitting polyelectrolyte layer and coagulation, caused by interparticle bridging. The aggregation effects could be suppressed by a large excess of the polycation in highly diluted systems. The amount of bound polyelectrolyte was determined via a subsequent polyelectrolyte complex formation. Possible determinants of the structure of the polyelectrolyte layer are discussed.It is a well-known fact that in highly diluted systems latex particles may be covered with a layer of water-soluble polymers, preventing coagulation. This makes it possible to study the structural parameters of the polymer layer by static and dynamic light scattering. Killmann et al. (7) could show that the thickness of the adsorbed layer of poly(ethyleneoxide)s on polystyrene latexes depends strongly on the amount of the adsorbed polymer and still more on the molecular weight of the polymer. The strong Coulombic interaction between a charged latex surface and an oppositely charged polyelectrolyte impedes the suppression of coagulation effects. Main objectives of this paper are :-coating of a charged latex with a polyelectrolyte without coagulation -study of the structural parameters of the polymer layer , using static and dynamic light scattering -determination of the amount of bound polyelectrolyte by subsequent polyelectrolyte complex formation