Synthesis and surface properties of a series of surfactants based on O-alkyl and O-perfluoro-N,N′-diisopropylisoureas

O-Dodecyl-N,N′-diisopropylisourea and O-tridecafluorooctyl-N,N′-diisopropylisourea were synthesized by reaction of hydrogenated or fluorinated alcohols onto diisopropylcarbodiimide in quasi-quantitative yields. Adding various hydrogen halides (HCl, HBr, or HI) onto these isoureas enabled one to obtain isoureas hydrohalides with tensioactive properties. The surface properties of both series of hydrogenated and fluorinated surfactants were studied and compared. The influence of the counter-ions onto the surface properties showed that the tensioactive properties were improved in the following increasing order: I < Cl < Br. Fluorinated isourea hydrohalides exhibited better surfactant properties than their hydrogenated homologues.