Structural and Viscoelastic Properties of Semifluorinated Alkane Monolayers at the Air/Water Interface

The structural and viscoelastic properties of monolayers at the air/water interface are of substantial interest from a scientific point of view, as well as of paramount importance for technological applications from soap films to surface coatings.
We currently investigate the class of semifluorinated alkanes at the air/water interface in order to develop a detailed structure-properties relationship for this very particular class of materials.
Such semifluorinated alkanes are linear alkanes, which carry in one half of the molecular chain fluorine atoms instead of hydrogen. Due to the incompatibility of the fluorocarbon and hydrocarbon fragments, such molecules are considered amphiphobic and tend to locally phase separate into intriguing 3D and 2D structures. This intrinsic structuring capability is anticipated as novel building motif in supramolecular architectures.
For this purpose it is of fundamental importance to understand the structural and dynamic behaviour of these molecules, which we try to assess in monolayers at the air/water interface of a Langmuir trough in combination with an interfacial stress rheometer (ISR). While the structural organization was investigated on the water by neutron reflectivity and after transfer to solid substrates by atomic force microscopy, the rheological behaviour was studied for the floating Langmuir film by the ISR.

    

Collaboration Partners:

Prof. Dr. Dimitris Vlassopoulos - Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure & Laser (IESL), P.O. Box 1527, 71110 Heraklion, Greece - and - Department of Materials Science and Technology, University of Crete, Heraklion, Greece

Dr. Thomas Geue - Paul Scherrer Institut, Laboratory for Neutron Scattering, 5232 Villigen, Switzerland

Prof. Dr. Klaus Müllen - Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany

Dr. Rüdiger Berger and Prof. Dr. Hans-Jürgen Butt - Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany