| abstract |
Enamine gp.-contg.prepolymers are made by reacting mono-enamines contg. free hydroxyl or amino gps., with polyisocyanates. Pref. mono-enamine starting materials have the formula (I) or (II) in which R is H or CH3. Suitable polyisocyanates are TDI, 4,4-diiso-cyanatodi phenylmethane, capped aromatic dissocyanates, aliphatic diisocyanates such as hexamethylenediisocyanate, cycloaliphatic diisocyanates, such as isophorone diisocyanate, biuret gp.-contg. triisocyanates, isocyanate prepolymers made by reacting excess diisocyanate with polyester or polyethers, etc. The enamine gp.-contg. prepolymers form stable mixts. with opt. capped organic polyisocyanates to give moisture-curing compsns. useful eg as lacquers, primers, sealants, coatings, etc., which cure on mixing with water or on exposure to atmospheric moisture without liberating heat. |