Adhesion, description

Adhesive Description Curing Method Special Characteristics Usual Adherends Price Range... 

Adhesive Description Curing method Special characteristics Usual adherenda l iice range... 

Company Adhesive Description Typical Uses Cure rc) Service No. 

Poly(ethyl methacrylate) (PEMA) yields truly compatible blends with poly(vinyl acetate) up to 20% PEMA concentration (133). Synergistic improvement in material properties was observed. Poly(ethylene oxide) forms compatible homogeneous blends with poly(vinyl acetate) (134). The T of the blends and the crystaUizabiUty of the PEO depend on the composition. The miscibility window of poly(vinyl acetate) and its copolymers with alkyl acrylates can be broadened through the incorporation of acryUc acid as a third component (135). A description of compatible and incompatible blends of poly(vinyl acetate) and other copolymers has been compiled (136). Blends of poly(vinyl acetate) copolymers with urethanes can provide improved heat resistance to the product providing reduced creep rates in adhesives used for vinyl laminating (137). 

As previously mentioned, electrodynamic interactions, such as those arising from London forces, can also contribute to the adhesion of particles. These forces are dominated by dipole interactions and are broadly lumped into the classification known as van der Waals interactions. A more detailed description of van der Waals interactions than can be presented in this article is given in books by Israelachvili [95] and by Rimai and Quesnel [96]. 

Baney, J.M., Hui, C.Y. and Cohen, C., Experimental investigations of a stress intensity factor based description of the adhesion of viscoelastic materials. Langmuir, 17(3), 681-687 (2001). 

This chapter reviews the main aspects of rubber base adhesives. A detailed description of the main ingredients of rubber base adhesive has been given because most of the previous contributions in this area did not consider this important aspect. On the other hand, update of the literature in water-base rubber adhesives has been done. 

A general description of the three major classes of MDI s and brief descriptions of adhesive applications are shown in Table 1. More recently, MDl has become the isocyanate of choice in adhesives, partly because MDI has a lower vapor pressure than TDI does (see pp. 296-297 in [18]). Isocyanates have been shown to cause an allergic reaction in a small percentage of the population. This reaction can manifest itself in the form of an asthmatic condition [19]. Before starting work with isocyanates, researchers are encouraged to read about the proper precautions to take, in order to work safely with these materials. Researchers should also check with their local health and environmental safety representatives [20]. 

Mackey and Weil provide the general formula for a NR-P tape adhesive as shown in Table 9 ([210], Table 21, p. 219). They also give brief descriptions of the various grades of nitrile rubber available. 

The section on chemistry of adhesives evolves from rubber-based adhesives to semi- structural and finally to structural adhesives. Everaerts and Clemens provide a thorough description of chemistry and applications of pressure sensitive adhesives and Kinning and Schneider describe an enabling technology for pressure... 

Qnantized adhesion was observed by Hoh et al. [53] for a SisN4 tip breaking contact with a glass snrface in water, which had been NaOH adjusted to pH 8.5. As described at the beginning of Section IILA, a more accurate description of the measurement would be quantized displacement, which can be evaluated as quantized adhesion by multiplying the observed displacement by the lever stiffness. The authors speculate that their observations conld be explained either by the breaking of discrete numbers of hydrogen bonds between the tip and surface or by the breakdown of the continuum properties of water in close proximity to a solid surface. 

X-cut According to ASTM D 3359, method A, an X is cut into the film to the substrate, pressure tape (TESAPACK 4287) is applied over the X and then removed, and adhesion is evaluated by comparison with descriptions and pictures. The method is used to establish whether the adhesion failure of the coating to the substrate may occur between the coats (adhesive break) or in the coating (cohesive break). 

The adhesion proteins are divided into a number of different groups. The main groups are the integrins, cadherins, immunoglobulin superfamily group, selec-tins, and CD44. A brief description of each of these types of adhesion proteins now follows. 

The familiar positive photoresists. Hunt s HPR, Shipley s Microposit, Azoplate s AZ etc., are all two-component, resist systems, consisting of a phenolic resin matrix material and a diazonaphthoquinone sensitizer. The matrix material is essentially inert to photochemistry and was chosen for its film-forming, adhesion, chemical and thermal resistance characteristics. The chemistry of the resist action only occurs in the sensitizer molecule, the diazonaphthoquinone. A detailed description of these materials, their chemical structures and radiation chemistry will be discussed in Section 3.5.b. 

The preceding has been a description of our efforts to develop a screening test for adhesives which will be used on steel or monel substrates which are maintained at a cathodic potential, immersed in... 

Although numerous studies (1-3) have described work aimed at establishing criteria for the durability of adhesive joints, a thorough understanding of effects of the chemical and mechanical properties, on the durability of adhesive bonds is lacking. More specifically, the effects of surface preparation and dynamic loading, especially under environmental service conditions, has not been explored in detail for automotive structures. In this paper, a description of the effects of environment on the durability of adhesive bonds is presented. Particular attention is given to... 

A selective method of preventing the expression of adhesion molecules or cytokines is the use of antisense oligonucleotides. These oligonucleotides are short sequences of nucleic acids complementary to mRNA sequences of specific proteins of interest. If delivered to the cytoplasmic compartment of cells these oligonucleotides are able to form a complex with their target mRNA. In this way the translation of mRNA into protein by ribosomes is inhibited. The subsequent mRNA degradation by RNAse H results in reduced expression of the protein (see also Chapter 5 for a description of antisense ohgonucleotides as therapeutic modalities). 

FIGURE 13.9 Descriptions of simple tensile detachment (a) and simple lap shear (b) assemblies for testing adhesion. 

The science behind bonding technology is very extensive. A brief description along with some examples is given in the following text. It is important to prime the surfaces of the layers to be bonded, that is, cover the surfaces with a dilute solution of the adhesive mixed with an organic solvent to obtain a dried film of thickness between 0.0015 and 0.005 mm. 

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