Highly reactive liquid uretdione groups-containing polyurethane systems which are curable at low temperature

摘要

Highly reactive, liquid, uretedione group-containing polyurethane compositions containing a catalyst selected from quat. ammonium carboxylates, quat. ammonium hydroxides or fluorides, and metal hydroxides or alcoholates. Highly-reactive, liquid, uretedione group-containing polyurethane compositions (I) with a melting point below 40[deg]C, containing (A) uretedione group-containing hardener(s) based on aliphatic, (cyclo)aliphatic or cycloaliphatic polyisocyanates and hydroxy compounds, with a free NCO content of less than 5 wt% and a uretedione content of 1-18 wt%, (B) 0.001-5 wt% catalyst(s) (optionally encapsulated in an inert shell), (C) optionally polymers with hydroxyl or amino groups and an OH (or amino) number of 20-500 mg KOH/g, (D) optionally 0.1-10 wt% compound(s) which react with acid groups, (E) optionally 0.1-10 wt% monomeric or polymeric acid(s), (F) optionally solvents and (G) optionally additives etc. Catalysts (B) comprise (B1) compounds of formula (1), (B2) compounds of formula (2) or (B3) compounds of formula (3) [NR 1R 2R 3R 4] + [R 5COO] - (1) R 1-R 41-18C alkyl, aryl, aralkyl, heteroaryl or alkoxyalkyl (all optionally linear or branched and/or bridged with other groups R 1-R 4 to form mono-, bi- or tri- cyclic systems which may also contain hetero-atoms, and/or containing alcohol, amino, ester, keto, thio, acid, urethane, urea or allophanate groups, double or triple bonds and/or halogen atoms); and R 51-18C alkyl, aryl, aralkyl, heteroaryl or alkoxyalkyl (all optionally containing groups, bonds or atoms as above) [NR 1R 2R 3R 4] + [R 5] - (2) R 1-R 4as above; and R 5OH or F M(OR 1) n(OR 2) m(OR 3) o(OR 4) p(OR 5) q(OR 6) r (3) M : a metal in any positive oxidation state, identical with the sum of n-r; m, o, p, q, r : 0-6; (n+m+o+p+q+r) : 1-6; and R 1-R 6H or 1-8C alkyl, aryl, aralkyl, heteroaryl or alkoxyalkyl (optionally bridged and/or substituted as above). Independent claims are also included for the following: (1) a method for the production of (I) in heatable reactors at temperatures below 130[deg]C; and (2) compositions containing (I) for coating metal, wood, glass, leather or plastics.