Specific adhesion

Adhesion, specific Adhesion between surfaces whereby valence forces predominate that are similar to those promoting cohesion. 

PLASTEC s staff of specialists offers professional services in a wide range of interest such as packaging, electronics, deterioration (eg — weathering, microbiological, compatibility), new materials, composites, foams, adhesives, specifications, test methods, tooling and processing, etc. At the direction of DoD these technical services are available to the entire US scientific and technical community... 

Fannon, A M. and Colman, D. R. A model for central synaptic junctional complex formation based on the differential adhesive specificities of the cadherins. Neuron 17 423 34,1996. 

Ball, USP 2,643,611(1953) CA 47,9016 (1953)(Inhibitor strips for large-grain rocket propellants are attached by means of an adhesive consisting of NC dissolved in Et lactate, cello solve, mesiryl oxide, Bu acetate or diacetone alcohol. These solvents act as a mutual plasticiser for the material of the inhibitor strip and for the propellant itself) 5)G.Epstein, "Adhesive Bonding of Metals," Reinhold, NY(1954> 6)ASTM Committee D-l4on Adhesives, Standards on Adhesives, Specifications, Physical Tests, Definitions, Philadelphia, Penna(1954) 7)... 

The early aerospace adhesives were primarily based on epoxy resin chemistry. However, unique applications requiring high temperatures and fatigue resistance have forced the development of epoxy-phenolic, epoxy-nitrile, epoxy-nylon, and epoxy-vinyl adhesives specifically for this industry. The aerospace industry has led in the development and utilization of these epoxy-hybrid adhesives. 

Most adhesives used for weldbonding are arbitrarily selected from adhesives that were developed for other purposes, resulting in a compromise when used for weldbonding. Adhesives specifically developed for weldbonding should have the following characteristics in addition to those mentioned above ... 

The outdoor durability of epoxy bonded joints is very dependent on the type of epoxy adhesive, specific formulation, nature of the surface preparation, and specific environmental conditions encountered in service. The data shown in Fig. 15.19, for a two-part room temperature cured polyamide epoxy adhesive with a variety of fillers, illustrates the differences in performance that can occur due to formulation changes. Excellent outdoor durability is provided on aluminum adherends when chromic-sulfuric acid etch or other chemical pretreatments are used. 

DeFrayne, G. O., Adhesive Specification and Quality Control, in Adhesives in Manufacturing, G. L. Schneberger, ed., Marcel Dekker, New York, 1983. 

The addition of the nitrogen-containing crosslinking agents, melamine, urea, and urea-formaldehyde (UF) resin, resulted in a substantial increase in strength (Table III, entries 7-12). The best results were obtained by the melamine-crosslinked adhesives. The addition of 33% melamine resulted in an adhesive with strength values well within exterior-grade adhesive specifications. 

Bisphenol A (chemically similar to MDA but having -OH groups rather than amine groups) was identified in the water and 3% acetic extracts from Sample 2. Bisphenol A was not detected in the extracts from Sample 1. Infrared transmission spectra recorded through Samples 1 and 2 showed that the MDl isocyanate was slower to react in Sample 2 and so the bisphenol A could possibly relate to the laminating adhesive. As a result, LC-MS tests were undertaken later in the research, on extracts from Sample 3 (laminated with the same adhesive) specifically looking for bisphenol A - none was detected. Tri-ethyl phosphate, thought to be used as a cure catalyst, was identified in the extracts from both Sample 1 and Sample 2. 

Hynes, R.O. and Lander, A.D. (1992). Contact and adhesive specificities in the associations, migrations, and targeting of cells and axons. Cell 68, 303 322. 

A semi-permanent screen print adhesive Specifications ... 

Kakoulides EP, Smart JD, Tsibouldis J. Azocrosslinked poly(acrylic acid) for colonic delivery and adhesion specificity in vitro degradation and preliminary ex vivo bioadhesion studies. J Control Release 1998 54 95-109. 

Haataja S, Tikkanen K, Liukkonen J et al. (1993) Characterization of a novel bacterial adhesion specificity of Streptococcus suis recognizing blood group P receptor oligosaccharides. J Biol Chem 268 4311—4317... 

Most historical surveys treat the work of McBain and Hopkins in 1925 as the earliest application of modern scientific investigation to the study of adhesion [9]. McBain and Hopkins considered that there were two kinds of adhesion, specific and mechanical. Specific adhesion involved interaction between the surface and the adhesive this might be chemical or adsorption or mere wetting. Specific adhesion has developed into the model we today describe in terms of the adsorption theory. 

One typical concern with acrylic adhesives, specifically those containing methyl methacrylate as a component, is the characteristic odor of the methyl methacrylate monomer. This odor may be objectionable to some people and may result in the use of other types of adhesives instead. Later in this chapter some of the new low odor formulations will be briefly discussed as alternative adhesives where odor has been an issue. This new technology offers performance characteristics equal to methyl methacrylate-containing products, albeit at a higher price. 

Adhesion—The state in which two surfaces are held together by interfacial forces which may consist of valence forces, or interlocking action, or both. (See also adhesion, mechanical and adhesion, specific.) The state in which two surfaces are held together by chemical, or physical forces, or both, with the aid of an adhesive. The attraction between substances which, when they are brought into contact, makes it necessary to do work to separate them. 

Adhesion, mechanical—Adhesion between surfaces in which the adhesive holds the parts together by interlocking action. (See also adhesion, specific.)... 

Adhesion, specific—(sometimes called adhesion, molecular). Adhesion between surfaces which are held together by valence forces of the same type as those which give rise to cohesion. (See also adhesion, mechanical.)... 

Table 7.10 lists common recommended surface treatments for plastic adherends. These treatments are necessary when plastics are to be joined with adhesives. Specific surface treatments for certain plastics and their effect on surface property characteristics are discussed in Sec. 7.6. Details regarding the surface treatment process parameters may also be found in ASTM D-2093 and various texts on adhesive bonding of plastics. An excellent source of information regarding prebond surface treatments is the suppher of the plastic resin that is being joined. 

Engineering design with adhesives C WATSON Advantages of use of adhesives specific examples of improved design... 

See also adhesion, mechanical, and adhesion, specific G Adhasion f, F adhesion f, S adhesion f, I adesione f. ... 

---