POLYURETHANE SYSTEMS HAVING NON-SAG, PAINTABILITY, AND PRIMERLESS ADHESION ON CONCRETE

摘要

A two part non-sag polyurethane construction sealant or adhesive is provided with the properties of low modulus, high elongation, good paint adhesion, and primerless adhesion to concrete surfaces. The sealant or adhesive is prepared using a polyol, and optionally an epoxy silane and/or a melamine compound, in the base component of the formulation; and a prepolymer reaction product including the residues of xylenol or xylenol and an additional polyol, and a polymeric isocyanate, an aromatic diisocyanate, or a polymeric isocyanate and an aromatic diisocyanate, and optionally an epoxy silane and/or a melamine compound, in the activator component of the formulation.