Non-Sticking Polymeric Surfaces: Dynamics of Nano Structured Fluorinated Polymeric Thin Films

The adhesion characteristics of interfaces of structured co-polymers is essential for many coating applications. These interfaces consist of domains of all segments, each with its unique characteristic adhesion, where the overall interfacial behavior depends on the dynamics at the boundary. While in simple liquids interfacial dynamic is well captured by capillary waves, increasing complexity of the polymers result in interfacial dynamics that is affected by the structure of the macromolecules in the film. Here we report Xray Photon Corelation Spectroscopy (XPCS) study of the interfacial dynamics of thin liquid films of semi-fluorinated polymer melts that consist of alternating fluorinated and protonated segments. The interface of these polymers exhibit nano-structured H and F domains, whose size depend on the segment length. We find that despite the fact that in average fluorinated segments reduce surface tension, the interfacial dynamics differs from that of capillary waves, where increasing the fraction of fluorinated segments reduces the fluctuations.