Derivatives of poly(sodium acrylate) bearing a few mole percent of perfluoroalkyl side chains were synthesized. Their solution properties were investigated by rheology and compared to those of their hydrogenated analogues. As the hydrogenated modified polymers, these new materials display an associating behavior. In semidilute solution the modified polymer exhibits viscosities of several orders of magnitude higher than the unmodified poly(sodium acrylate). However, this viscosifying effect is more pronounced for the perfluorinated derivatives. By comparing the rheological behaviors we find that a polymer bearing C7F15CH2 side groups is as associative as a polymer containing the same fraction of C13H27 chains. This is in agreement with Ravey and Stébé's1 conclusions concerning surfactant association that a CF2 is equivalent to 1.7CH2 as regards its hydrophobicity. Mixtures of the perfluorinated polymers with their hydrogenated analogues or with hydrogenated surfactants were successively studied. For low modification ratios (≤7 mol %) and at concentration ranges close to the critical aggregation concentration the mixing is not ideal. This is in line with the nonideal behavior displayed by mixtures of perfluorinated and hydrogenated surfactants.

New perfluoroalkyl double-chain surfactants were synthesized based on trisubstituted perfluoroalkylated thiourea. These amphiphiles have a modular structure consisting of hydrophobic tails, thiourea as connector, alkyl spacer, and ammonium head group. The modular organization allows an independent variation of the key features in the amphiphilic structure. The synthesis strategy was based on the condensation reaction of 2-(F-alkyl)ethyl isothiocyanates with 3-(dimethylamino)-N-(2-hydroxy-2-F-alkyl)ethyl)alkylamines and subsequent quatemization by methyl iodide to produce the trisubstituted perfluoroalkylated thiourea. The two reaction steps proceed with high yields. The surface activity properties of the new amphiphiles were studied and the ability to self-assemble into bilayer vesicles was determined by freeze fracture electron microscopy and quasi-elastic light scattering.

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