Adhesion is the tendency of certain dissimiliar molecules to cling together due to attractive forces. Mechanisms of adhesion Five mechanisms have been proposed to explain why one material sticks to another: Mechanical adhesion Adhesive materials fill the voids or pores of the surfaces and hold surfaces together by interlocking. Sewing forms a large scale mechanical bond, velcro forms one on a medium scale, and some textile adhesives form one at a small scale. This is similar to surface tension… (More on Adhesion)