Лако-красочные материалы — производство

Latent catalysts used in conjunction with either liquid or solid resins are cast in thin films on plastic or release paper for unsupported films or onto absorbent papers or cloths for supported films and then cured to B stage. These films can subsequently be cut to shape and placed between mating surfaces for subsequent heat […]

Excellent electrical insulation makes epoxy systems suitable for potting and encapsulation of electrical and electronic components. Here use is made of one-pack epoxies employing latent curing agents such as dicyandiamide. At the curing temperature the system will have very low initial viscosity, ensuring good wetting and bubble release. The low residual stresses protect components from […]

Epoxies find many applications in industry, especially on the engineering side. Grouting of bolts into concrete or rock surfaces, either to strengthen a rock face or for fixing of heavy machinery, is a common application. Such adhesives are usually filled systems, often using reactive hardeners to achieve rapid setting. Epoxy systems for horizontal grouting will […]

Epoxy adhesives find applications in various aspects of road making. Two major areas are bullnosing and fixing of reflective road studs. Bullnosing requires a system with good impact and compressive strengths and a pot-life time of 1 to 4h. Cast masses are on the order of 5 to 25 kg, so low-exotherm systems should be […]

While construction applications usually require reactive hardener systems to give good room-temperature cure, many metal bonding applications require strength at elevated temperatures. Usually, however, they also permit heat curing and postcuring. Surface preparation is crucial to achieving high bond strength and will always involve at least degreasing and abrading. Because of the high strength of […]

Water-based epoxy primers are ideal for damp porous substrates, as such primers will penetrate to an adequate depth to ensure good adhesion and produce a sound surface for bonding. Emulsifiable resins and hardeners are available, and the better systems deactivate the emulsifier system during cure to ensure that the cured system is not unduly water […]

Occasionally, elastomers may be included in solvent-based formulations. Poly(vinyl butyral) improves adhesion to metal, as does nitrile rubber, while natural and synthetic rubbers may be incorporated to improve flexibility. II. APPLICATIONS Epoxy resin adhesives are used mainly in niche applications rather than as general-purpose adhesives. Due to the high strengths that can be achieved and […]

Additives are typically products added at levels of 0.1 to 0.5% to modify specific proper­ties. Most commonly used additives are defoamers, antisettling or wetting agents, thixo- tropes, and adhesion promoters. Use of antioxidants or preservatives is rare. Because of their minimal shrinkage, compressive strength of cured epoxies is very high. Since aeration will reduce this […]

Although a major advantage of epoxy adhesives is their ability to be formulated without solvents, under certain circumstances solvents may be included. On porous substrates solvents may be added to reduce viscosity and assist penetration. On certain nonporous substrates, particularly some plastics, addition of a small percentage (1 to 3%) of a suitable solvent will […]

Two types of fillers may be incorporated into formulated epoxy systems. Powder fillers are added to increase viscosity, improve abrasion resistance and gap-filling properties, impart specific electrical or mechanical properties, or reduce cost and shrinkage. Addition levels may be 50 to 300 parts by weight of resin (phr). Although most fillers will increase the density […]