Results of microgravity investigation on adsorption and interfacial rheology of soluble surfactants from the experiment FAST onboard STS-107

Microgravity offers ideal diffusive conditions for the investigation of the dynamic processes involving surfactant adsorption. Here a summary of the results obtained during the FAST (Facility for Adsorption and Surface Tension studies) experiments on board the NASA Shuttle STS-107 is given. The measured data pertinent to interfacial rheology - i.e., the response of dynamic interfacial/surface tension to imposed perturbation of the interfacial area - for water-hexane and water-air interfaces, in the presence of different non-ionic surfactants are reported and utilised to test available models and to check fundamental aspects of the modelling of dilational rheology.