Some of us just don’t care how adhesives work. They work and that’s all we need to know. Some of us are what we would call armchair scientists, and we read technical manuals full of terminology that sounds like a foreign language to the average citizen.

Most of us probably fall somewhere in between. We like to know how things work, but we don’t want to go to a science college.

So for the curious layman, here is an overview of how industrial adhesives work:

Obviously, an adhesive is a compound that adheres, joins or joins two or more elements (or better, if they do not want us to change the brand), everyone knows it. It is the science behind it that not everyone is familiar with. Stickers work in four ways. The most common are mechanical and chemical bonds.

Mechanical bonding

The simplest and most common form of adhesion. In mechanical bonding, the bond that forms between the adhesive and the surface occurs when the adhesive penetrates the small pores on the surface. It acts as if millions of microscopic screws and bolts are driven into both surfaces to hold them together.

Chemical bond

Chemical bonding is when an adhesive actually bonds to the surface at the molecular level. This would be the same thing that happens when two hydrogen atoms join with an oxygen atom, therefore H2O or water. Certain chemicals simply attract each other. Hydrogen especially has a tendency to bond with any other atom you find out there.

The little-used alternatives

The third and fourth methods that are used infrequently include the use of van der Waals forces and diffusion of the adhesive with the aid of moisture on the surface of … well … well, the third and fourth are somewhat difficult to explain in plain terms, and they’re not very common anyway, so let’s talk about the first two for now.

A little more about mechanical bonding

Mechanical bonding does not occur strictly on a microscopic scale. Velcro, zippers, pins, staples, safety pins, and buttons are all forms of mechanical bonding. Mechanical refers to the fact that it is simply a physical form that holds the two surfaces together, like a pair of hands clenched tightly.

In glues and adhesives, mechanical adhesion through the pores of the surfaces occurs thanks to the drying or curing process. When the glue is turned on, it is in a thin liquid adhesive form, which still allows either surface to move freely. This liquid form also allows the adhesive to penetrate the pores on the surface. When it starts to dry out and solidify, it works, like velcro, as a bunch of hooks that hold the two objects together.

One more thing about chemical adhesion

Chemical bonding is more complex and only occurs on a microscopic scale. It works by forming a compound between the chemicals on the two surfaces. The reason this shape is not that popular with epoxy adhesive manufacturers should be obvious. Chemical bonding happens all the time in nature, but it is a difficult thing to design in your spare time. Only certain chemicals can be easily bonded together, and artificial adhesives to aid in chemical bonding are still a relatively unknown frontier.