The competitive displacement mechanism

On theoretical grounds, the phenomenon of two-phase coexistence at a liquid interface in a complex mixed adsorbing system is certainly not unexpected. So long as the various molecular interactions are of the normally expected form, statistical thermodynamics indicates that interfacial demixing can readily lead to a more favoured stable equilibrium state (Pugnaloni et al., 2004). 

Based on experimental evidence from AFM, the physical mechanism of orogenic5 displacement was proposed (Mackie et al., 1999b, 2000, 2003). A crucial aspect of the mechanism is that the surfactant domains exert a lateral surface pressure which compresses the protein layer. The AFM data obtained by Mackie and co-workers (1999b) provided direct visual evidence, for the first time, of a gel-like protein network at the air-water interface, as well as a structural explanation of protein displacement by small-molecule surfactant. In essence, the process of orogenic5 displacement is assumed to involve three stages  

These detailed AFM studies of the structure of surfactant + protein layers have helped to explain the followings observations  

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