Improved polyurethane reactive adhesives - comprises particulate poly:isocyanate(s) with deactivated surface, chain lengthener(s), polyurethane catalysts and additives

摘要

Polyurethane (PU) reactive adhesives comprise (A) particulate polyisocyanates with deactivated surface; (B) isocyanate-reactive cpds. of mol. wt. above 400; (C) opt. a chain lengthener(s) of mol. wt. below 400; (D) opt. PU catalysts; and (E) opt. conventional additives. The novelty is that the compsn. also contains epoxy-, SH-, NH- or NH2-gp. contg. alkoxysilane. The adhesion of substrates with a PU reactive adhesive contg. at least one adhesive as above is also claimed. The alkoxysilane contains two or three (m)ethoxy gps. and one or more (m)ethyl gps. per silicon atom, and contains a bound aminoalkyl gp. with one, two or more NH or NH2 gps. on the silicon atom. (A) has a m.pt. of above 80 deg.C and has an isocyanate gp. equiv. of 0.1-2.5. (B) is polyols and/or polyamines. ADVANTAGE - Provides improved adhesion between adhesive and substrate without disadvantageous effe