Uretdione-group-containing polyurethane compositions which are cross-linkable at low temperatures

摘要

Highly reactive, 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, uretedione group-containing polyurethane compositions (I) with a melting point above 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) and (F) optionally additives etc. Catalysts (B) comprise (B1) compounds of formula (1), (B2) compounds of formula (2), or (B3) compounds of formula (3). [NR 1>R 2>R 3>R 4>] +> [R 5>COO] -> (1) R 1>-R 4>1-18C 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 con tain 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 5>1-18C alkyl, aryl, aralkyl, heteroaryl or alkoxyalkyl (all optionally containing groups, bonds or atoms as above). [NR 1>R 2>R 3>R 4>] +> [R 5>] -> (2) R 1>-R 4>as above; and R 5>OH 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 6>H 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; (2) compositions containing (I) for coating metal, wood, glass, leather or plastics; and (3) polyurethane coating powder or adhesive compositions containing (I).