Ketimine Latent Amine (Moisture-Cure)

Ketimine Latent Amine is a blocked amine curing agent produced by reacting a polyamine (such as DETA or TETA) with a ketone (e.g., methyl isobutyl ketone, MIBK), forming an imine (Schiff base) that is latent at ambient conditions. When exposed to atmospheric moisture, the imine hydrolysis regenerates the free amine in situ, which then cures the epoxy resin. This moisture-activated mechanism enables one-component (1K) epoxy formulations that are stable in the can but cure upon exposure to ambient humidity. Ketimine hardeners are especially valuable in 1K coatings, sealants, and adhesives for maintenance applications where 2-component mixing is impractical. They are also used in moisture-cure composite repair films and in prepreg-style single-component laminates. The cure rate depends on ambient relative humidity — at 50% RH and 20°C, full cure typically requires 24–48 hours. Low humidity conditions (<30% RH) significantly slow or prevent cure. Pot life of the mixed system (if any accelerator is added) is effectively unlimited as long as moisture ingress is prevented. Particularly useful for field maintenance, pipe wrap, and emergency repair composites.