Adhesives classification

Another kind of adhesive classification will be given in Section 3.3, Figure 3.7. 

In addition to the criteria of the adhesive classification given in Section 2.2, another subdivision by the kind of adhesive layer or polymer properties formed by the adhesives is possible based on the aforementioned explanations (Figure 3.7, supplemented by typical adhesive raw materials). 

Although there are many adhesives, there are only four main adhesive classifications, i.e. animal, vegetable, mineral and synthetic. 

Modification of properties in acryUc adhesives is more often conducted at the chemical level, through changes in formulation or combination with other base resins. Wide ranging properties can include impact resistance, surface insensitivity, environmental resistance, etc. The emergence of urethane acrylate adhesives, as well as acrylated epoxies, begins to make simplistic adhesive classifications more challenging. 

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

Chapters 4-6 describe the adhesives available from a materials standpoint. In Chapter 4, adhesive classification in a number of ways has been described according to the source, function, chemical composition, physical form, and application. Chapter 5 discusses individual adhesive types in detail. As a matter of convenience, the adhesives have been arranged in alphabetical order. Chapter 6 describes adhesives for specific adherend types. 

Adhesives may be classified by various methods such as function, chemical composition, mode of application and setting, physical form, cost, and end use. The most common methods of adhesive classification are summarized in Table 7.6 (p. 7.22). 

Lamination (sticking together of layers) of fabric, foam and film, in various combinations, can be performed using latex- and solvent-based or fusible adhesives (see Adhesive classification). In addition, adhesives are sometimes applied from solution or latex for subsequent reactivation by heat during lamination. Acrylic dispersions are the main type of latex-based adhesives used in the laminating industry butadiene rubbers and polyurethanes are also utilized in smaller quantities. The latex-based adhesives are used for aesthetic reasons and also on heat-sensitive or open-structured fabrics. The solvent-based adhesives, for example rubbers and polyurethanes, are used in applications similar to those for latex adhesives. 

These types of adhesives can be broadly classified by their physical form of application and/or the way they are activated to form a bond with the material to which they are applied, for example, as emulsion polymers, solution polymers, hot melts and reactive polymers (see Adhesive classification). Each of these will now be considered in turn. 

Further details appear in other articles. Emulsion and dispersion adhesives. Solvent-based adhesives, Adhesive classification. Hot melt adhesives, Rubber-hased adhesives. 

Further details regarding the advantages and limitations of different adhesives are given in articles already cited and in the articles listed below. Other sources include Refs. [2-4] and works discussed in the Appendix. See also Adhesive classification, Anaerobic adhesives, Cyanoacrylate adhesives. High-temperature adhesives, Rubber-based adhesives. 

Adhesive classification B C COPE Classified by setting mode and chemical nature... 

Adhesives can also be broadly classified as being thermoplastic, thermosetting, elastomeric, and alloy blends. These four adhesive classifications can be further divided by specific chonical composition, as shown in Appendix K. 

Adhesives can be broadly classified as being thermoplastic, thermosetting, elastomeric, or alloy blend. These four adhesive classifications can be further subdivided by specific chemical composition as described in Tables 7.20 through 7.23. The types of resins that go into the thermosetting and alloy adhesive classes are noted for high strength, creep resistance, and resistance to environments such as heat, moisture, solvents, and oils. Then-physical properties are weU suited for structural-adhesive applications. 

Service requirements. Adhesives must also be selected with regard to the type of stress and environmental conditions to which they wiU be exposed. These factors will further limit the number of candidate adhesives to be tested. Information on the envi-ronmental resistance of various adhesive classifications wiU appear in the next section. 

L17-500 1991 Aerospace series. Structural adhesives. Classification and qualification. 

Remark on the comparison between adhesives and sealants. One can consider that even if the main properties of sealants differ from the ones addressed by glued joints the mechanisms involved to create the bonding are the same. Controlled chemistry is needed to reach the best level of interactions and formulations are improved to reach the required visco-elastic properties. The mechanism involved in the building of the joint is mainly based on chemical reactions. Nethertheless, the major difference between sealants and adhesives concerns the properties of the resulting joints that are not only adhesion properties. The fact that (1) the sealant joints are much more thicker than glued joints and that (2) additional properties such as, for example, watertightness or vibration absorbing lead us to separate the sealant family from the adhesive classification. 

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