Adsorption of Ionic Surfactants onto Hydrophilic Surfaces

Adsorption of Ionic Surfactants onto Hydrophilic Surfaces 

This was only possible at the higher coverage measured (at cmc). At the lower concentration ( 50% coverage), it was not possible to make that distinction, and this suggests that at the lower coverage, the surface consists of small islands (bilayer patches) of surfactant on the surface (as depicted in Fig. 5). Estimates of those lateral dimensions are consistent with that expected for surface micelles of CieTAB. 

Atkin et al. [57] have recently produced a comprehensive review of the mechanisms of cationic adsorption at the solid-solution interface, and made a detailed comparison between AFM, neutron reflectivity, fluorescence quenching, 

The ability to manipulate the neutron refractive index, through D/H isotopic substitution, makes neutron reflectivity and small angle scattering powerful techniques for the study of surfactant mixtures, and this has been extensively exploited in the study of adsorption at the air-water interface [17] and in micelles. 

In contrast to the measurements by McDermott et al [58], neutron reflectivity measurements for the Ci2E6/Ci6TAB mixture in 0.1 M NaBr at the air-water interface and SANS measurements of the mixed micelles show close to ideal mixing. Penfold et al. [60] has used neutron reflectivity to investigate this mixture at the solid-solution interface. For the hydrophilic silicon surface, the surface composition of the mixed surfactant bilayer adsorbed at the interface depended strongly upon the solution pH. At pH 2.4, the surface composition 

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