Laura Martin

Prof. Julian Eastoe

Interfacial properties of fluorinated surfactants and polymers in organic solvents.

The interfacial adsorption and micellisation properties of both monodisperse non-ionic fluoro-surfactants and fluorinated polymers have investigated in both aqueous and non-aqueous solvents.  The low MW surfactants compounds were fully or partially fluoroalkyl triethyleneoxide methyl ethers.  In water the fluorocarbon chains drive a strong solvophobicity, and the compounds behave like classic surfactants [1].  In an organic solvent (methyl ethyl ketone - MEK) a weak solvophobicity is evident due to fluorocarbon-hydrocarbon incompatibility; adsorption at the solvent-air interface can be detected by surface tension measurements and neutron reflectivity from the adsorbed layers.  Similar experiments were conducted on single MW bolaform and Y-shaped surfactants.  These surfactants have widely different molecular architectures.  Finally, fluorinated polymers were studied at the MEK/air interface.  The results show that the behaviour in organic solvents of fluorocarbon surfactants and polymers of this kind is very similar to that of classical surfactants in water.

Laura is funded by the EPSRC and a Kodak CASE award.

1) Eastoe, J., Paul, A., Rankin, A., Wat, R., Penfold, J. and Webster, J.R.P., Langmuir, 2001, 17, 7873