The Laws of Molecular Adhesion

All atoms and molecules adhere with considerable force. More simply, if two solid bodies approach to nanometer separations, then they will jump 

The effect of contaminant wetting molecules is to reduce adhesion, or even to make the bodies repel each other. In other words, adhesives reduce molecular adhesion. 

Molecular adhesion forces are of such short range that various mechanisms can have large effects. Examples of such mechanisms are surface roughness. Brownian motion, cracking, viscous deformation, etc. These mechanisms lead to a rich variety of adhesion phenomena which may cause macroscopic adhesion to vary, even though the molecular adhesion remains the same. 

These laws at first sight seem to go against our common experience. Indeed, they may seem to be incorrect when seen for the first time. Rather like Newton s laws of motion, the above statements strip away the interference of other effects such as gravity, friction, viscosity and geometry which dominate our everyday experience. They reveal the chemical reality of natural electronic forces between atoms. 

Just as Perrin concluded that a fluid s apparent repose is merely an illusion because the fluid molecules are in a state of eternal and spontaneous motion, so must we believe that all molecules adhere strongly, even though macroscopic objects appear nonsticky. The apparent lack of adhesion we see in engineering situations is really an illusion because adhesion is universal at the molecular level, according to the first law of adhesion above. However, there is a serious conundrum here because it seems impossible that particles can be in constant Brownian movement, where it is necessary for particles to collide and bounce off each other, yet also sticking together, which would cause agglomeration and 

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