Organic based adhesives

Static Adhesion Tests for Organic-Based Yarns, Cords, and Fabrics. The most commonly used static adhesion tests are the H-test... 

Cyanoacrylate adhesives cure by anionic polymerization. This reaction is catalyzed by weak bases (such as water), so the adhesives are generally stabilized by the inclusion of a weak acid in the formulation. While adhesion of cyanoacrylates to bare metals and many polymers is excellent, bonding to polyolefins requires a surface modifying primer. Solutions of chlorinated polyolefin oligomers, fran-sition metal complexes, and organic bases such as tertiary amines can greatly enhance cyanoacrylate adhesion to these surfaces [72]. The solvent is a critical component of these primers, as solvent swelling of the surface facilitates inter-... 

Surface Modifications. Basic photopolymer chemistry is also being used for the surface modification of films, textiles fibers, and many other organic-based materials (104). Some of the novel applications of photopolymer technology to surface modification include the design of cell repellent treatments and in photografting of various chemical functionality onto the surface of materials to improve color retention, enhance the adhesion of antistatic chemicals or to improve staining resistance. 

Structure and function of the cell formations of higher organisms are highly dependent on adhesive interactions based on direct cell-cell contact and on interactions of cells with the extracellular matrix. Adhesion between cells and with the extracellular matrix has a regulatory influence on migratory behavior, proliferation and differentiation of an individual cell within the cell formation. The adhesion processes thus do not only serve to simply hold cells together in the formation. They also have a regulatory effect... 

Adhesive, Electrically Conductive, Silver Organic Base Adhesive, Synthetic Rubber, Buna N Type... 

Adhesives Organic and inorganic bases Coolants Cleaners colorants (pigments and dyes) Fragrances Inks Paints Plasticisers (e.g., in plastics) Polymers (rubbers and plastics) Sealants Solvents Stabilisers Synthetic fibres Varnishes Biocides Detergents Fertilisers Fuels Foodstuff additives and flavourings to foodstuffs Medicinal products (for humans and animals) Plant protection products Radioactive substances... 

With improved formulations, organic-based conductive adhesives became feasible replacements for eutectic solders. Table 4 shows typical one- and two-part conductive adhesives from the 1970s. The one-part adhesive system employed a latent catalyst for long pot life but required a high-temperature cure cycle. The two-part system, formulated... 

Suitable magnetic strips or bar codes can be both writeable and readable by currently available equipment. In a degradable design, the card is desirably coated on at least one side with a film laminate that preferably comprises a biobased film, a biopolymer material, a cellulose film, or an organic-based film (6). Also, a pressure sensitive adhesive may be used that affixes the protective layer to the base layer in a manner that protects the annotation region from degradation (5). 

GPC is also a very useful technique for characterizing the molecular mass range/distribution of the various organic polymers and co-polymers used as thickeners in anaerobic, acrylic, and radiation-curable adhesives. The base polymer, tackifying resin, and petroleum wax components of hot-melt type adhesives may also be characterized in a similar manner. 

These materials are widely used because they are durable, fire-resistant, and inexpensive when compared with organic materials. Inorganic adhesives are based on compounds such as sodium silicate, magnesium oxychloride, lead oxide (litharge), sulfur, and various metallic phosphates. The characteristics of some of the more important commercial materials are summarized. 

Solvent-based adhesives are more expensive than water-based products. They usually make bonds that are more water-resistant and have higher tack and early strength than water-based adhesives. Solvent-based adhesives also wet oily surfaces and some plastics considerably better than water-based adhesives. Organic solvents must be handled in explosion-proof equipment and precautions need to be taken during application. Ventilation to remove toxic hazards must also be provided to avoid exposure of personnel to solvent vapors. ... 

Table 5.10 lists polymers used for both water- and solvent-based adhesives. Water-based adhesives cost less than the equivalent solvent-based compounds. Even inexpensive organic solvents are costly when compared to water. The use of water eliminates problems of flammability, emission, and toxicity associated with organic solvents. However, in most cases, water-based adhesives must be kept from freezing during shipment and storage because of possible permanent damage to both the container and the contents. 

Applications of NBR adhesives are based on the excellent elastomeric properties of the polymer coupled with its polarity, which provides good solvent resistance and compatibility with other polymers. Organic solutions of NBR are the most common adhesives, although water-borne and pre-cast films can also be nsed. 

Manufacture and compounding The majority of organic solvent-based adhesives are based on rubbery polymers, the main ones being natural rubber, polychloroprene, butadiene-acrylonitrile, styrene-butadiene and polyisobutylene. Traditionally, the rubber was placed in a heavy-duty mixer and solvent was added slowly till a smooth solution was formed. In some cases, the rubber was milled beforehand to reduce viscosity and produce smoother solutions. Nowadays, it is possible to obtain some grades of material that only require stirring in a comparatively simple chums. 

However, Fig. 1 also shows that when the fluid air is replaced by the fluid water, a more serious problem is presented. Water, because of its relatively high surface tension (when compared with liquid organic-based adhesive for example), is much more strongly adsorbed by highly energetic surfaces and is a mnch more difficult contaminant to displace. 

The research has been done with financial support fiom Ministry of Education and Science of the Russian Federation imder realization of the federal special-purpose program Scientific, academic and teaching staff of irmovative Russia for 2009-2013 years The Grant Agreement J T 14.B37.21.0837 Development of active adhesive compositions based on element organic polymers and vinyl monomers. ... 

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