ADHESIVES PRODUCED USING ASPARTATE-TERMINATED PREPOLYMERS

Provided are adhesives comprising: (A) an aliphatic polyisocyanate; and (B) an aspartate-terminated prepolymer which is a reaction product of (B1) an aliphatic NCO-terminated prepolymer having a NCO content of from 0.5% to 35%, and (B2) a compound according to formula (I)wherein, X represents a linear or branched aliphatic group obtained by removing amino groups from a linear or branched aliphatic polyamine, R1 and R2 are identical or different and represent organic groups which are inert towards isocyanate groups at a temperature of 100° C. or less, R3 and R4 are identical or different and represent hydrogen or organic groups which are inert towards isocyanate groups at a temperature of 100° C. or less, n represents an integer with a value of at least 2, wherein the aspartate-terminated prepolymer (B) has a ratio of equivalents of NH groups to equivalents of NCO groups of 1.5:1 to 20:1, (C) optionally, a solvent, wherein the adhesive has a ratio of equivalents of NCO groups in the aliphatic polyisocyanate to equivalents of NH groups of from 0.9:1 to 1.75:1, wherein pot life of the adhesive, as measured by doubling of viscosity according to ASTM D4212-16 at 23° C., is greater than or equal to 0.5 hours, and wherein the adhesive develops an acceptable bond strength to a substrate, defined as having a minimum of 150 g/in. measured @ 23° C. according to ASTM D 1876-01 or substrate tear, in less than or equal to 5 days after the substrate is laminated with the adhesive.