Egg as an Adhesive

In my previous post I asked about what an emulsifier is and why egg yolk is one. I found the answer one this website: http://www.exploratorium.edu/cooking/eggs/eggscience.html. Emulsions are mixtures of liquids that do not mix well together. Egg yolk contains many different proteins such as Lecithin that stabilize the emulsion and allow the two mixtures to disperse with one another. A common example of an emulsion is oil in water mixture. Oil does not mix well with water and so an emulsifier is need for the oil to be dispersed in the water. With egg yolk you create a binder for these two liquids. In paint, egg yolk and water are mixed to create an adhesive. Paint stick on to its painting medium because of this adhesive. Plus, paint is a binder for the pigment. This is a great website for a short simple explanation of emulsions. It turns out emulsions are part of a bigger type of mixture called colloids. All I know about them is that they are heterogeneous mixtures that compose of matter mixing with another unmixable matter. They can consist of any state of matter except a gas with gas mixture. This website also mentioned how an emulsifier stabilizes the system. But it never mentioned how it does that, so why does an emulsifier stabilize an emulsion? Why is egg yolk such a great emulsifier?