Discrete Nanoscale Distribution of Hair Lipids Fails to Provide Humidity Resistance.

The subcellular distribution of lipids in human hair was investigated to better understand their role in water permeability. Unlike where lipids are organized under a precisely ordered continuous structure, the removal of free lipids in hair does not lead to an increase of water permeability. Esterified and CH-enriched molecules were tracked at a 10 nm resolution by infrared nanospectroscopy (atomic force microscopy coupled to infrared spectroscopy, AFMIR).

Turning autophobic wetting on biomimetic surfaces into complete wetting by wetting additives.

Autophobicity or pseudo partial wetting, a phenomenon of a liquid not spreading on its own monolayer, is characterized by an energy barrier that prevents the growth of a wetting film beyond the monolayer thickness. Applying a molecularly detailed self-consistent field theory we illustrate how autophobic wetting can be overcome by wetting additives. More specifically we use an emulsifier which keeps the interfacial tension between the wetting component and the majority solvent low, and a co-solvent additive which partitions inside the film and then destroys the molecular order in it so that the barrier for film growth is cleared.