Adhesive markets

In the electrical and electronic equipment market, adhesives compete with other joining methods such as mechanical fasteners, brazing, welding, soldering, and thermocompression bonding. Major uses of adhesives in the electrical and electronic equipment market are shown in Table 1.5. Adhesives are generally the preferred method of joining whenever... 

Lohman, R. J., Weldbonding Leads Growth of Structural Adhesives in Auto Market, Adhesives Sealants Industry, May 1997, pp. 30-34. 

One property that almost every ink must possess is adhesion to whatever media it is being printed upon. In both the graphic arts and industrial printing markets, adhesion to plastics ranks high on the list of requirements. 

The OEM automotive business is directed at marketing adhesives and sealants through the final assembly of the vehicle, whereas the automotive aftermarket sells products to dealers, professional repair shops and do-it-yourself stores. 

The new steel panels used in vehicles are not as heavy as in older cars but, being thinner, are not as strong. The use of PU windshield adhesive/sealants to replace the traditional butyl sealants has enabled the windshield to become a structural part of the vehicle because it supports the roof. OEM adhesives are typically one-component moisture-cured urethanes that take several hours to cure and give bonds with tensile shear strengths of 5-8 MPa. The products are pigmented black to give resistance to UV. After-market adhesives... 

Adhesives and sealants are a multi-billion dollar industry that serves many applications and end-markets. Adhesives are used in a huge variety of industries, from automotive to medical and from electrical switchgear to sports goods. 

Laminated Strand Products. The most recent developments in the family of wood-based composites are a group of laminated strand products, made with strands oriented in the long direction of the product and marketed as stmctural composite lumber. One product is made with long, narrow strips of softwood veneer. The strips or strands are about 2.5 x 13 x 600 mm (0.1 x 0.5 x 24 in.), coated with a PRE adhesive, and pressed under heat and pressure into large blocks. After the resin is cured the blocks are resawn and planed into lumber dimension stock. 

Emulsion Polymerization. Emulsion polymerization is the most important industrial method for the preparation of acryhc polymers. The principal markets for aqueous dispersion polymers made by emulsion polymerization of acryhc esters are the paint, paper, adhesives, textile, floor pohsh, and leather industries, where they are used principally as coatings or binders. Copolymers of either ethyl acrylate or butyl acrylate with methyl methacrylate are most common. 

The largest market for elastomer-based adhesives is that of lamination (see Laminates). Modem office furniture having Formica as a surfacing material is made with an elastomer-based adhesive. Tile adhesives for ceramic or carpet tile are also elastomer-based and usually solvent appHed. Paper adhesives and shoe manufacture also use substantial quantities of mbber-based materials. Solvent-weld adhesives are used to join plastic plumbing and to repair vinyl sheeting. 

Polyurethanes. About 3% of the U.S. polyurethanes market in 1988 was derived from the condensation product of polyisocyanates with low molecular weight polyadipates having hydroxyl end groups (195). In 1986 this amounted to 29,000 t, or 4% of total adipic acid consumption. The percentage was similar in Western Europe. About 90% of these adipic acid containing polyurethanes are used in flexible or semirigid foams and elastomers, with the remainder used in adhesives, coatings, and spandex fibers. 

Amino and Phenolic Resins. The largest use of formaldehyde is in the manufacture of urea—formaldehyde, phenol—formaldehyde, and melamine—formaldehyde resins, accounting for over one-half (51%) of the total demand (115). These resins find use as adhesives for binding wood products that comprise particle board, fiber board, and plywood. Plywood is the largest market for phenol—formaldehyde resins particle board is the largest for urea—formaldehyde resins. Under certain conditions, urea—formaldehyde resins may release formaldehyde that has been alleged to create health or environmental problems (see Amino RESINS AND PLASTICS). 

PBI is being marketed as a replacement for asbestos and as a high temperature filtration fabric with exceUent textile apparel properties. The synthesis of whoUy aromatic polybenzimidazoles with improved thermal stabUities was reported in 1961 (12). The Non-MetaUic Materials and Manufacturing Technology Division of the U.S. Air Force Materials Laboratory, Wright-Patterson Air Force Base, awarded a contract to the Narmco Research and Development Division of the Whittaker Corp. for development of these materials into high temperature adhesives and laminates. 

The principal chemical markets for acetylene at present are its uses in the preparation of vinyl chloride, vinyl acetate, and 1,4-butanediol. Polymers from these monomers reach the consumer in the form of surface coatings (paints, films, sheets, or textiles), containers, pipe, electrical wire insulation, adhesives, and many other products which total biUions of kg. The acetylene routes to these monomers were once dominant but have been largely displaced by newer processes based on olefinic starting materials. 

The uniqueness of methyl methacrylate as a plastic component accounts for its industrial use in this capacity, and it far exceeds the combined volume of all of the other methacrylates. In addition to plastics, the various methacrylate polymers also find appHcation in sizable markets as diverse as lubricating oil additives, surface coatings (qv), impregnates, adhesives (qv), binders, sealers (see Sealants), and floor poHshes. It is impossible to segregate the total methacrylate polymer market because many of the polymers produced are copolymers with acrylates and other monomers. The total 1991 production capacity of methyl methacrylate in the United States was estimated at 585,000 t/yr. The worldwide production in 1991 was estimated at about 1,785,000 t/yr (3). 

Another market appHcation for naphthenic acid is the tire industry, where cobalt naphthenate is used as an adhesion promoter (see Adhesives Tire cords). Cobalt naphthenate improves the bonding of brass-plated steel cords to mbber, presumably by suppressing the de-zincification of brass (50). Its first reported use was in 1970 and the first patent for its use was issued in 1975 (51). About 900 t of cobalt naphthenate is used worldwide as an adhesion promoter, half of it in North America. The unit value fluctuates between 8.75—13.25 /kg because of the volatility of cobalt prices. Although it is the industry standard, the use of cobalt naphthenate is declining with the advent of more economical high metal-containing substitutes. 

In the other market areas, lead naphthenates are used on a limited basis in extreme pressure additives for lubricating oils and greases. Sodium and potassium naphthenates are used in emulsiftable oils, where they have the advantage over fatty acid soaps of having improved disinfectant properties. Catalyst uses include cobalt naphthenate as a cross-linking catalyst in adhesives (52) and manganese naphthenate as an oxidation catalyst (35). Metal naphthenates are also being used in the hydroconversion of heavy petroleum fractions (53,54) and bitumens (55). 

Adhesives and Sealants. Dominated by copolymers, adhesives and sealants remain somewhat of a specialty market. These polymers usually... 

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