Single-component Polyurethane adhesive

One-component polyurethane adhesives have also become popular in recent years. These adhesives have a single component and depend on moisture for curing. The moisture is sometimes available in the wood or the atmosphere, but it is common practice to dampen the surface before applying the adhesive. One has to be careful to use the right amount of adhesive and to clamp the parts, because the adhesive generates foam on curing and tends to expand. 

The most important types of two-component adhesives are moisture-sensitive polyurethane, comprising polyol resin and isocyanate catalyst, and heat-sensitive epoxy, comprising bisphenol A or F resins and polyamine catalyst. Both single- and two-component adhesive systems are available in the market. Single-component reactive adhesives, which include cyanoacrylate and silicone, are also widely known, with the latter often being used as a sealant. 

UV-sensitive adhesives are based on acrylate-modified epoxy resins, polyurethane, and amongst others, polymers. They are single-component reactive adhesives, which undergo rapid polymerization upon irradiation with UV light with wavelengths ranging from 400 to 500 nm. These adhesives should be stored in small opaque containers of up to 50 mL in volume. They can be stored in their original containers for 6 months at 10-25°C. 

Solvent cementing is usually used with these materials. Conventional adhesives recommended include single- and two-component polyurethanes, cyanoacrylates (Loctite 430 Superbonder), epoxies, and silicone rubbers. 

The blocked isocyanate function of aminimides also allows their use as polyurethane adhesives. Thus bis(aminimides) crosslink with polyester or polyether diols to yield a range of elastomers dependent upon the structure of the bis(aminimide) and the co-reactant chosen. For example, bis(aminimides) mixed with polyhydroxyl components can provide stable, single-package prepolymer compositions which yield polyurethanes on heating without the problem of isocyanate moisture sensitivity which can plague polyurethane applications. 

Polyurethane Adhesives. The search for formaldehyde-ffee binders resulted in a new generation of polyurethane-based glues for chipboard production. The usage of polyurethane based adhesives for assembly of wooden materials has also increased. These liquid polyurethane adhesives are single-component adhesives that harden by a chemical cross-linking reaction which is initiated by moisture in the material. The water... 

Tile Adhesives. The thin-set process uses hydraulically hardening thin-set mortars based on cements, emulsion adhesives based on aqueous synthetic resin emulsions, which can be single-component ready to use tile adhesives or two-component adhesives consisting of modified aqueous emulsions and a cement-based compound, and reactive adhesives based on epoxy resins or polyurethanes. 

Single-component adhesives polyurethane 15-25°C (Cooling chamber/room temperature)... 

Polyurethane adhesives for plastics are available primarily in both single-component and two-component forms. They are very tough, flexible products with excellent peel strength and are also extremely versatile for the bonding of larger plastic components. 

Adhesive applicator systems for applying single-component adhesives can be fed by either a pressure-feed container for light viscosity adhesives or ram-mounted drum pumps for medium to heavy viscosity adhesives. Application can be manual or automatic. Multiple-component adhesives, such as epoxy resins, polyurethanes, and silicones can be processed by piston or gear-type metering and mixing adhesive dispensing systems [6]. 

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