Fast-setting adhesives

The most suitable in any particular instance is best established by trials in advance. Sometimes, fairly severe abrasion (by increasing the surface area available) is the most successful. On the other hand, excessive roughening may weaken the substrate and so give inferior results. With fast-setting adhesives like the cyanoacrylates, microscopic bubbles of air may be trapped between adhesives and substrate and so impair bonds. 

In the case of fast-setting adhesives and large adherends, possibility of curing starting prior to fixation of the adherends... 

These liquid resins then work at a resorcinol content of only 9 to 11%, hence considerably lower than that of traditional PRF resins. These resins can also be used with good results for honeymoon fast-setting adhesives in PRF tannin systems, thus further decreasing the total content of resorcinol in the total resin system at a level as... 

Uses Epoxy curing agenl/hardener used for laminates, coatings, fast-set adhesives, castings, pottings, and tooling compds. 

Chem. Descrip. Modified aliphatic amine Uses Epoxy curing agent for laminates, fast-set adhesives, castings, and tooling compds. accelerator for Genamid 250,490,747 Features Offers faster cure times, lower reaction temps. exc. chem. and heat resist. 

Epoxy resins n. Plastic or resinous materials used for strong, fast-setting adhesives, as heat resistant coatings and binders, etc. Cross-linking resins based on the reactivity of the epoxides group. One common type is the resin made from epichlorohydrin and bisphenol A. Aliphatic polyols such as glycerol may be used instead of the aromatic bisphenol A or bisphenol F. 

Methyl-2-cyanoacrylate n. A fast setting adhesive used for bonding cellulosics, nylon, polyesters, acrylics, polystyrene, and polyurethanes to each other and to other materials such as woods, metals, and glass. Catalyzed by atmospheric moisture or lightly applied methanol, the adhesive polymerizes without loss of solvent. For best results, the surfaces to be bonded should mate closely. 

After this survey of the different types of UV-curable resins that can be used as adhesives, and the way they undergo rapid cross-hnking upon illumination, we will now review the main applications of such fast-setting adhesives in various industrial sectors. 

Pizzi A, Rossouw D duT, Knuffel W E, Singmin M 1980 Honeymoon phenolic and tannin-based fast-setting adhesive systems for exterior grade fingerjoints. Holzforsch Holzverwert 32 140-150... 

Pizzi A, Roux D G 1978 The chemistry and development of tannin-based weather and boil-proof cold-setting and fast-setting adhesives for wood. J Appl Polym Sci 22 1945-1954... 

Adhesives for Automatic Pacicaging Machines. In automatic packaging, package production, filling, and closing are often carried out in a single machine. For this reason, very fast setting adhesives are used. 

Fast setting adhesive with high temperature service level. 

Electronic parts are so tiny that only mini droplets of fast setting adhesives and sealants need to be used for their assembly and, although each piece of equipment uses only grams (or less) of adhesives, when multiplied by the huge number of units produced, it comprises a very big market in terms of Dollars or Euros. 

Thus the quoted data for a commercial acrylic depending on polymerization of a monomer or mixture of monomers gives 2 days at 15°C or 1 h at 80°C, both with 2% catalyst however, an increase of the catalyst to 5% reduces the cure time at 80°C to 25 min. R/F adhesives may, in the presence of a catalyst, require several hours at room temperature while curing in a few minutes at the moderately elevated temperature of 80°C. By working at, say, 105°C this becomes a fast setting adhesive with a cure time of about a minute. Scheme 2 can therefore provide only a rough classification. 

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