Typical Formulation Ingredients
Ingredient
Parts by weight
Epoxy resin (Epikote 880, Shell)
Polyurethane resin (Desmocap 11, Bayer)
Latent epoxy curing agent (Eurodur 43, Schering, AG)
Dialkylamine epoxy curing agent (Anchor 1110, Anchor Chemicals)
Plasticizer, dibutyl phthalate
(Source: Mittal, K. and Pizzi, A., eds., Handbook of Sealant Technology, CRC Press, New York, 2009, p. 442)
Resulting Properties
Polyurethanes are extensively and successfully used as adhesives and sealants, and they have an excellent record of durability. Blocked prepolymers are used in some of these formulations. At room temperature these blocked compounds do not react with the polyol, thus providing long shelf life. The blocked polyurethane systems can be applied either in the form of 100% solids, solution, or aqueous systems using elevated temperatures to deblock the isocyanate which then reacts with the other components.