Simple, reactive amphiphilic molecules were prepared by condensation of perfluorooctylethyl alcohol with elaidic, oleic, and linoleic acids. The fluorinated, unsaturated esters were found to be surface active in polyester and urethane-modified alkyd coatings. In addition, they function much like typical drying ails used in these coatings through oxidative cross-linking. The surfaces of the coatings were examined by contact angle goniometry and X-ray photoelectron and time-of-flight secondary ion mass spectroscopy. The solution properties of these fluorinated derivatives were studied by measurement of surface tension isotherms, vapor pressure osmometry, and variable temperature F-19 NMR spectroscopy in n-butyl acetate solution. Analysis of the data revealed that aggregation is occurring at low ( < 10(-1) mol/L) solute concentration. The aggregates were small and ranged between 3 and 7 monomer units. Analysis of the variable temperature F-19 NMR data for the linoleic acid ester gave thermodynamic parameters for aggregation of Delta G(a)degrees approximate to -4.30 +/- 0.2 kcal/mol, Delta H(a)degrees approximate to 6.11 +/- 2 cal/mol, and Delta S(a)degrees approximate to 15.7 +/- 0.8 cal/(mol.K).
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