Bimolecular Primer Urethane-Isocyanurate Adhesive Composition with High Temperature Resistance

摘要

The two-component polyurethane compositions have good storage stability and the adhesives prepared by curing the compositions have good high temperature stability and do not lose their adhesiveness even after high temperature baking. In addition, the substrate or prepolymer component containing the primary hydroxyl intermediate should be sufficiently high such that the OH curable group in the curing agent component + the ratio of free NCO groups in the prepolymer component to all amine groups is generally from about 1.2 to about 2.0, . The curing agent component contains a trimerization catalyst so that isocyanate units are formed upon curing. The system also contains molecular sieves as well as adjuvant adhesion promoters.