Adsorption from Solution and Monolayer Formation

You are living on a plane. What you style Flatland is the vast level surface of what / may call a fluid, on, or in, the top of which you and your countrymen move about, without rising above it or falling below it. 

1a Surfactant Layers Langmuir and Gibbs Layers and Langmuir-Blodgett Films 

Until now, we have avoided considering the above topics by intentionally excluding solutes of variable concentration from our consideration of surfaces. Now, the effects of such solutes are our specific interest. We are especially concerned with a particular class of solutes that show dramatic effects on surface tension. These are said to be surface active and are often simply called surfactants. Our primary emphasis here is on the relationship between adsorp- 

Traditionally, monolayer and multilayer adsorption have been used in detergency, mineral processing, flotation, stability of food and pharmaceutical emulsions, and the like, and, as a consequence, the topics of this chapter have been a central part of colloid science. In recent years, however, research on monolayer and multilayer deposition has mushroomed rapidly because of significant new opportunities. 

At the most fundamental level, monolayers of surfactants at an air-liquid interface serve as model systems to examine condensed matter phenomena. As we see briefly in Section 7.4, a rich variety of phases and structures occurs in such films, and phenomena such as nucleation, dendritic growth, and crystallization can be studied by a number of methods. Moreover, monolayers and bilayers of lipids can be used to model biological membranes and to produce vesicles and liposomes for potential applications in artificial blood substitutes and drug delivery systems (see, for example, Vignette 1.3 on liposomes in Chapter 1). 

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