Urethane based adhesives

Acrylic acid based Urethane based Adhesive resistant to fuels Heiner and Coates EP 741005, 1995 3M... 

CHEMISTRY, DURABILITY OF STRUCTURAL ADHESIVE BONDS Urethane Based Adhesives... 

Urethane acrylates Urethane adhesives Urethane alkyds Urethane-based resins... 

Effect of moisture cure on properties of a urethane-based hot melt adhesive... 

Commonly used adhesives include epoxy, rubber, acrylic or vinyl emulsions, and urethanes. Epoxies are high-priced, but they have better chemical resistance and durability than the others, and they have dominated the market in outdoor applications. Significant advantages of the epoxy-based adhesives are that they have no solvents and, therefore, exhibit little shrinkage. They cure relatively fast and, therefore, are not as exposed to inclement... 

Bisphenol A epoxy based and related materials are used in two-part urethane epoxy adhesives. 

An urethane-based pressure-sensitive adhesive composed of a liquid hydroxytelechelic polybutadiene and a polyisocyanate does not require a solvent in coatings onto label sheets. This polymer together with the (polystyrene-co-butadiene) copolymer and a polyisocyanate was applied in steel coatings 239 240>. 

There are two different bonding systems employed with the block a urethane asphalt adhesive/membrane or a special inorganic silica-based mortar. The choice depends on mechanical considerations and on the chemical and thermal environment. 

Isocyanate-Based Adhesives. Generally diisocyanates or polyisocyanates are used in the preparation of polyurethane adhesives. The urethane link (-O-C(O)-NH-) is formed by the reaction of an alcohol with an isocyanate (-N = C = 0) group ... 

ZDEC is used in the following applications as a fast primary or secondary vulcanization accelerator in NR, SBR, IIR, EPDM and for natural and synthetic latex a stabilizer in butyl, butadiene, and urethane rubbers an antioxidant in rubber-based adhesive systems a stabilizer in cement a heat stabilizer for polyethylene. 

In the U.S. converting industry, one- and two-component solvent-based adhesives are still the most widely used, accounting for nearly 80% of adhesive formulations. Many of these adhesives are typically polyester-or polyether-based urethanes (see Chapter 4) with isocyanate fimctionaHty that cure by reacting either with atmospheric moisture or a cross-linker. Polyether-based urethanes, while less expensive than polyester-based, do not provide the same strength and do not perform well in some processing environments or end uses. 

Water-based adhesives also encompass emulsion and dispersion adhesives in which polymer chains are dispersed and stabilized into tiny particles or spheres in aqueous medium with the aid of surfactants. Within this category there are low-cost poly(vinyl acetate) and acrylics, and more expensive higher-performance urethanes, which are typically made of two components. 

In our previous work with inductively and capacitively coupled plasmas at low pressures [40], it was shown that N2-containing plasmas produced considerable adhesion improvement (>50%) between waterborne urethane/acrylate coating and sugar maple. XPS studies further indicated a considerable amount of grafted nitrogen atoms which are likely to allow covalent bonding between urethane-based... 

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