The 10 nm liquid-like layer in thin polymer films does not exist, reflectivity can prove it

Since the discovery (1994) of liquid-like layers in glassy polymers there has been a persistent dogma that a 10 nm liquid like layer exists at the surface of supported polymer thin films. This liquid-like layer manifests as a significant reduction (~ 10°C -30°C) in the glass transition temperature (Tg) of an ultra-thin film, this means orders of magnitude increase in polymer mobility and dynamics. We have evidence which shows this phenomenon simply does not exist and is instead an artefact due to fundamental limitations with the technique originally used to prove its existence, ellipsometry. Unifying our results from ellipsometry with neutron and X-ray reflectivity will unambigously show that when measured correctly, there is no reduction in the Tg of a thin film. Such work is of huge importance and will necessitate re-writing the textbooks in the field.