Interfacial layers from the protein HFBII hydrophobin: Dynamic surface tension, dilatational elasticity and relaxation times

► After expansion, surface tension relaxes exponentially indicating barrier control. ► The barrier is due to the energy of monomer detachment from a HFBII tetramer. ► After compression, the surface tension relaxation indicates diffusion control. ► This could be surface diffusion during HFBII “condensation” on surface aggregates. ► The condensation reduces the dilatational elasticity at higher surface pressures.