Water-borne urethane adhesives

Mor-Ad [Morton], TM for a series of adhesives consisting of solvent-free-one component urethane, cross-linked water-borne epoxy, and polypropylene bonding adhesives. 

Chem. Descrip. y-Glycidoxypropyltrimethoxysilane CAS 2530-83-8 EINECS/ELINCS 219-784-2 Uses Adhesion promoter in water-borne acrylic sealants, urethane and epoxy coatings coupling agent in polysulfide and polyurethane caulks and sealants, min.-filled or glass-reinforced thermosets and thermoplastics, and in glass roving size-binders Properties Colorless transparent liq. m.w. 236.4 dens. 1.065-1.075 vise. 

As with pressure sensitive adhesives, general purpose water-borne adhesives often involve blend combinations to yield the desired balance of properties for a myriad of applications. An evaluation of three emulsions (acrylic, epoxy and a urethane) (using a simplex blending study) was conducted for polyester/LLDPE, polyester/nylon and A1 foil/polyester lamination [142]. In each lamination, a ternary blend gave the optimized performance when a number of properties were considered. 

Almost all urethane materials are synthesized without the use of solvents or water as diluents or earners and are referred to as being 100% solids. This is true of all foams and elastomers. There are many products, however, which do utilize solvents or water, and these are known as solvent-borne and waterborne systems, respectively. In the past, many coatings, adhesives, and binders were formulated using a solvent to reduce viscosity and/or ease application. However, the use of volatile solvents has been dramatically curtailed in favor of more environmentally friendly water (see Section 4.1.3), and now there are many aqueous coatings, adhesives, and associated raw materials. Hydrophilic raw materials capable of being dispersed in water are called water reducible (or water dispersible), meaning they are sufficiently hydrophilic so as to be readily emulsified in water to form stable colloidal dispersions. 

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