There are many different ways of interaction between the physical bodies.One of these is the adhesion surface.Let's look at what this phenomenon and what it has properties.
What adhesion
definition becomes more clear if we figure out how the word was formed.With adhaesio Latin translates as "pull, grip adhesion."Thus, adhesion - it is nothing like the connection of heterogeneous condensed bodies, which occurs when they are in contact.When the contact surface of uniform, there is a special case of this interaction.He referred autohesion.In both cases it is possible to draw a clear line between the interface objects.In contrast, they secrete cohesion at which adhesion molecules within the material itself.To make it clearer, consider an example from the life.Take an ordinary PVA glue and water.Then put them on different parts of the same glass surface.In this example, water is a substance which is inherent poor adhesion.It is easy to check, turning the glass upside down.Cohesion also characterizes the strength of the material.If you glue the two pieces of glass glue, the connection will be reliable enough, but when you combine them with plasticine, the last tear in the middle.From what we can conclude that its cohesion to a strong link would be insufficient.We can say that these two forces are complementary.
Types adhesion and factors affecting its power
depending on what the body interact with one another, manifest certain features sticking.The highest value represents adhesion arising from the interaction with the solid surface.This feature is of practical value in the manufacture of various adhesives.Furthermore, still secrete adhesion of solids and liquids.There are several key factors that directly determine the force with which will manifest adhesion.This area of contact, the nature of the contacting surfaces and their properties.In addition, if at least one of the pair of objects carries the electric charge, the interaction will be a donor-acceptor bond, which will enhance the adhesion.A significant role is played by capillary condensation of water vapor on the surface.Due to this phenomenon between the substrate and the adhesive may occur chemical reaction that increases the bond strength.If a solid body dipped into the liquid, the consequence can be seen, which also causes adhesion, - a wetting.This phenomenon is often used for painting, gluing, soldering, lubrication, enriching rocks, etc.To eliminate adhesion lubricant is used, which prevents direct contact of the surfaces, and for its enhancement, on the contrary, activation of the surface produced by mechanical or chemical treatment, exposure to electromagnetic radiation or to add various functional impurities.Quantitatively, the degree of such interaction is determined by a force which must be applied in order to separate the contacting surfaces.In order to measure the adhesion force, a special device called adgeziometrami.The very same set of methods for determining it is called adgeziometrii.
