Industrial wood glues

The 2-imino-4-thiazolines may be used as ultraviolet-light stabilizers of polyolefin compositions (1026). 2-Aminothiazole improves adhesive properties of wood to wood glue (271). Cbmpound 428 exhibits antioxidant properties (Scheme 242) (1027). Ammonium N-(2-thiazolyl)dithio-carbamate (429) is a bactericide and fungicide used in industrial products such as lumber, paint, plastics, and textiles (1037). Compound 430 is reported (1038) to form an excellent volume of foam coating in aluminum pans when ignited with propane. 

The sensitizing potential of this preservative has been established in a modified Draize test (17% of 205 volunteers) (Maibach 1971). The industrial exposure is widespread (e. g., wood, leather, and tanning industries, wallpaper glue, nylon spin finish, cutting oils). Chloracetamide in cosmetics and pharmaceutical preparations has caused contact allergy (Nater 1971 Calnan 1971) of 27 contact allergic reactions to Hirudoid ointment 7 were caused by chloracetamide (Smeenk and Prins 1972),... 

Uses textile-finish resin of formaldehyde type for treatment of e.g., cotton and rayon materials in wood-glue industry... 

Acetic acid is one of the simplest carboxylic acids. It is an important chemical reagent and industrial chemical, used in the production of polyethylene terephthalate mainly used in soft drink bottles cellulose acetate, mainly for photographic film and polyvinyl acetate for wood glue, as well as synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents. In the food industry, acetic acid is used under the food additive code E260 as an acidity regulator and as a condiment. 

The casein wood glues have a long history of use as interior structural adhesives, assembly adhesives, and panel-to-frame adhesives. A limited but important use is as a nonconductive adhesive in the construction of spacers for the large transformer boards for the electrical industry. The most popular use of casein and protein blend glues is in the production of hollow and solid core flush doors, an operation for which these glues are ideally suited. Most of the doors in this country are made with this type of glue. 

Wood Glues. While wood glues are normally thought of in relationship to furniture and cabinet making, they have become important in construction also. Most finish carpenters utilize one of the various types of wood glues on trim around doors, windows, base board or other types of trim in the finishing process of construction, whether residential or industrial. 

Casein had been the basis of general-purpose wood glues, particularly in Switzerland and Germany, since the early 1800s but now their use was adopted, across the board, by the aircraft industry as assembly adhesives and glues for plywood. Fig. 5 shows a post-war application in the construction of a fully bonded rib this would have mirrored the military approach of a few years earlier. The... 

While the polyvinyl acetate-based emulsions have multiple applications (office glues, wood glues, packaging industry, etc.), the acrylic emulsions are used mainly for the production of autoadhesive films and tapes or for other labels (see PSAs part) their main value therefore lies in the large variety of formulations accessible (using variable composition copolymers) and in the good tolerance they demonstrate toward the plasticizers present in certain substrates (bonding of polyvinylchloride films for example). 

This natural adhesive is derived from fish skins, especially as a by-product of the cod industry. Fish glue is a weaker adhesive than animal glue, but it is interesting for certain applications, as a household adhesive that is able to adhere to glass, ceramics, metal, wood, cork, paper, and leather. One or both substrates have to be porous to allow the adhesive to dry or, alternatively, a remoistenable fish adhesive can be used. 

Polyvinyl acetate dispersions were produced on industrial scale in the 1930s and used as wood glues and later for high-speed packaging. In the 1950s latex house paints were introduced. 

From antiquity, glues had been made almost entirely from materials of animal or vegetable origin, and were sensitive to moisture, oxidation, and bacterial or fungus attack. Because of these deficiencies, production of durable plywood, for example, was not possible. The modern plywood industry actually owes its growth to the availabiUty of relatively low cost urea adhesives. Plywood and chipboard or wood chip glues are often made at the plywood and chip board mill. 

Adhesives based on isocyanate (especially PMDl, polymethylene diisocyanate, more exactly polymeric 4,4 -diphenylmethane diisocyanate) have been used for more than 25 years in the wood-based panel industry [88], but still have a low market value in the wood-working industry compared to systems based on UF-, MUF- or PF-resins. The main application is the production of waterproof panels, but also the production of panels from raw materials that are difficult to glue, like straw, bagasse, rice shells or sugar cane bagasse. They can be used as adhesives for wood-based products like particleboard, oriented strandboard (OSB), laminated strand lumber (LSL), medium-density fiberboard (MDF) or... 

Wood dust hazards and precautions COSHH and the woodworking industries Glue spreading machines Hardwood dust survey... 

Polymers are very large molecules made up of repeating units. A majority of the compounds produced by the chemical industry are ultimately used to prepare polymers. These human-made or synthetic polymers are the plastics (polyethylene, polystyrene), the adhesives (epoxy glue), the paints (acrylics), and the fibers (polyester, nylon) that we encounter many times each day. It is difficult to picture our lives without these materials. In addition to these synthetic polymers, natural polymers such as wood, rubber, cotton, and wool are all around us. And, of course, life itself depends on polymers such as carbohydrates, proteins, and DNA. This chapter discusses synthetic polymers. Naturally occurring polymers are presented in Chapters 25, 26, and 27. 

Despite the many consumer and wood gluing uses mentioned here, an estimated 75% of casein production went into paper coatings until World War II (4). Casein use for adhesives reached its peak in 1973, at about 121 million dry pounds (5). Today, very little casein glue is used by household consumers, paper coaters, and plywood manufacturers. In 1986, nearly all U.S.-casein adhesive production was used by the door manufacturing industry, where the total volume was less than 10 million pounds. 

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