PROCESSO PARA A PREPARACAO DE POLI-ISOCIANATOS CONTENDO GRUPOS IMINO-OXADIAZINODIONA PRODUTOS DO PROCESSO ASSIM PREPARADOS E SUA UTILIZACAO

A process for the production of polyisocyanates having at least 30 mol% iminooxadiazindione group content comprises use of a quat. ammonium and/or phosphonium fluoride catalyst with a solvating agent. A process for the production of polyisocyanates (I) containing at least 30 mol% iminooxadiazindione group (asymmetric trimer) (with respect to total quantity of isocyanurate and iminooxadiazindione groups), comprises catalytically induced trimerization of organic di-or polyisocyanates having an average mol. wt. of 140-600 g/mol and aliphatic and/or araliphatic bound isocyanate groups. The trimerization catalyst is a quat. ammonium and/or phosphonium fluoride of formula (1) which is used pure or mixed with a solvating agent (S) for the fluoride anion. (S) is a pure compound or a mixture of protic compounds having a pKa of greater than 2 (in H2O at 25 degrees C) or is oxalic acid but excluding higher functional alcohols (di and/or polyols) or HF. The molar ratio of (S) to F is no greater than 20. R4EF (1) E = N or P; R = 1-20C aliphatic, aromatic and/or araliphatic group, optionally forming saturated or unsaturated cyclic rings with N or P; n = 0.1-20