2 июля, 2015 
Malyar In addition to the stated theories of adhesion promotion, there are other mechanisms that may be both operative and important and are of general application.
1. Interpolymer Networks/Chain Tangling
It has been suggested that in the case of silane coupling agents, interdiffusion of siloxanol segments with polymer molecules may be a factor in bonding thermoplastic matrices. Interpenetrating polymer networks (IPNs) need not necessarily involve cross-linking of the silane or other coupling agent and the polymer matrix. Plueddemann expresses the view that to establish a strong interpenetrating boundary layer involves a tricky interplay of mechanical and chemical interreaction at the interface [16]. A similar mechanism has been suggested for titanates [17].
2. Acid-Base Reactions
A comprehensive account of acid-base reactions is covered in detail in volumes 4 (No. 4), 5, and 8 (1990) and volume 5 (No. 1) (1991) of the Journal of Adhesion Science and Technology and a detailed account is beyond the scope of this chapter. Since different metal oxides have different isoelectric points in water and may therefore be regarded as acidic or basic, addition of material having acidic properties to adhesives to be used on basic substrates, or basic materials for use on acidic substrates, may improve adhesion [25]. Work with epoxide and polyurethane coatings of similar composition to adhesives have shown them to be basic in nature; the pH of water-soaked surfaces from which they were stripped is known to be 8-10. The aminosilanes APES and AAMS are strongly basic and when applied to oxide surfaces having isoelectric points in the range 9.1 (A13+) to 12.0 (Fe2+) may be expected to produce a basic surface. Neither silane cou1d therefore be expected to enhance the adhesion of a basic polymer by an acid-base reaction, although both have been shown to improve the initial and wet adhesion of epoxides and urethanes. This is not to argue that acid-base reactions are unimportant in adhesion promotion technology.
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