The synthesis of multicompartment polymeric micelles (MCPMs) has been achieved by aqueous radical terpolymerization of a water-soluble monomer (acrylamide) with both hydrocarbon (H) and fluorocarbon (F) surfactants (surfmers) in the micellar state. The selected H- and F-surfmers are CH2CHCON(C2H5)CH2CH2N(CH3)2CH2COOC16H33/Br/Cl (HS6) and CH2CHCONHCH2CH2N(CH3)2CH2COOCH2CH2C8F17/Br (FS3), respectively. Their mutual incompatibility in aqueous solution has been checked by conductivity and surface tension experiments. Two cmc values are found, in favor of the coexistence of two distinct types of micelles at surfactant concentrations above 1 mmol/L (second cmc) over a broad composition range. The solubilization properties of the pure and mixed surfactant systems have been studied for different hydrophobic probes. Significant differences in the solubilization capacity occur due to the nature of the dye, of the surfactant, and of the micelle shape and composition. A kinetic study on the incorporation behavior of the H- and F-surfmers in the polyacrylamide backbone during a batch polymerization shows a compositional drift as a function of conversion which is attributed to micellar effects. A semicontinuous process has been designed which allows the correction for this compositional drift. The presence of well-segregated H- and F-microdomains in terpolymers could be inferred from viscosity and fluorescence experiments. Furthermore, the solubilization of decalin is enhanced in terpolymer solutions with respect to that of copolymer solutions. This was attributed to the formation of larger hydrocarbon cores in the former case due to repulsive H/F interactions in the polymeric chains.

A series of novel polymerizable hydrocarbon and fluorocarbon cationic surfactants (N-alkoxycarboxymethyl-N-[2-(N ′-alkylacrylamido)ethyl]-N,N-dimethylammonium bromide) potentially useful for the formation of multicompartment polymeric micelles were prepared. Micellization and surface active properties of these surfactants and of their mixtures were determined by electrical conductivity and surface tension measurements. The interaction between the fluorocarbon and the hydrocarbon surfactants in the aqueous micellar state can be described by the regular solution theory with an interaction parameter ) 1.25 indicating the formation of one type of mixed micelles. The solubilization capacity of the pure and of the mixed surfactant systems for pyrene and for a new fluorocarbon azo dye were studied by UV absorption as a function of the surfactant concentration. It was found that the ability to solubilize these hydrophobic compounds depends strongly on the nature of the micellar core (hydrocarbon, fluorocarbon, or mixed), the polarity of the dye, the micellar shape, and the composition of the surfactant mixture. Langmuir 1998, 14, 4765-4775 S0743-7463(98)00245-5 CCC: $15.00

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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