Classification of adhesives

The various structural possibilities of adhesives and the related variants of their processing amount to thousands of different compositions or formulations , which are applied in practice. This makes it difficult for the user to find the adequate adhesive, and thus it is often asked which adhesive is suitable for a certain material. The following description of the properties will facilitate the answer. 

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Figure 2.3 Classification of adhesives according to their way of curing.

Smith, J. D., Subramanian, G., Gamain, B., Baruch, D. I., and Miller, L. H. (2000a). Classification of adhesive domains in the Plasmodium falciparum erythrocyte membrane protein 1 family. Mol. Biochem. Parasitol. 110,293-310. 

Table 7.1 Classification of adhesive test methods—cant d... 

From the chemists has come the classification of adhesives and sealants by chemical type, and from the mechanical engineers the classification as either structural or non-structural. Neither is a pure system, since many adhesives and sealants have more than a single chemical base resin, and many structural -based resin systems are used in non-structural applications. In a chapter entitled Structural Adhesives we are told that the term structural adhesive came into general use in the 1960 1970 period, but to this day all definitions are inadequate [9, Chap. 7]. Adhesive manufacturers and their advertising... 

A Society of Manufacturing Engineers publication provides a useftil, in-depth classification of adhesives, as shown in the following tables. ... 

This chapter discusses individual adhesive types in detail. As a matter of convenience, the adhesives have been arranged in alphabetical order without regard to classification. See Chapter 4 for classification of adhesives. 

Definition of Adhesives and Adhesive Bonding Functions of Adhesives Classification of Adhesives Advantages and Disadvantages of Joining Using Adhesives... 

The classification of adhesives by hardening mechanism (Table 1) is probably the most informative, but a classification based on the chemical nature of the main polymer present is often used. Such systems require little explanation and might typically order materials first by the class of polymer, thermoset, thermoplastic or (thermoset) elastomeric, often with a separate class for natural polymers, and then snbdivide these classes according to the chemical structure. Table 2 shows how this might be accomplished. 

Classification of Adhesion. Adhesion is classified with respect to various indices, such as the properties of the medium, the forces determining adhesion, the number of adherent particles, the change in adhesion in the course of detachment, and the direction of the detaching force. 

A classification of adhesion according to the changes in the interaction between contiguous bodies in the course of detachment was given by Deryagin on the basis of the analogy between adhesion and friction [7, p. 186]. Friction prevents the tangential displacement of particles, and adhesion prevents the displacement of particles in a direction perpendicular to the surface on which they have been deposited. 

Table 13 Classification of adhesives by form and reaction mechanisms...

These three routes for the change of phase of an adhesive provide a very useful and common basis for classification of adhesives into solvent- and water-based, hot melt and reactive types. 

Every discipline develops its own specialized vocabulary and that of adhesion and adhesives is no exception. The terms relating to adhesives can be found in the glossaries of several handbooks on adhesives " the definitions most often used are based on those given in ASTM standard D-907, reproduced in Appendix I." In addition to terminology, there are a number of other topics that require some comment and these will be discussed in this introduction. They are the classification of adhesives, the selection of adhesives, and the choice of units. 

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