Contact interactions hydrophobic methylated surfaces

The methods and quantitative characteristics used in the analysis of the contact interactions between the particles can be applied to the processes involving the formation of sediments. This can be verified experimentally in sedimentation experiments with hydrophobic spherical particles (e.g., methylated glass or fluoropolymers) in a medium of a different polarity. The sedimentation of hydrophobic particles in low-polarity media, such as propanol or butanol, is of lyophilic type. The sedimentation of such particles in polar media, such as water or ethylene glycol, follows the lyophobic scheme. Similar to the case of experimental contact interaction studies, one can also observe a gradual transition from one type of sedimentation to the other. One particnlar example is the sedimentation of hydrophobic particles in aqueous solutions of alcohols. As the system becomes more lyophilic with the shift to alcohols with lower polarity or with an increase in the alcohol concentration, a transition from lyophobic sedimentation to lyophilic sedimentation takes place. A gradual decrease in the volume of the sediment is observed. Small additives of surfactants that make the surface of the particles hydrophilic have a similar effect. The concentration of an alcohol... 

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