| 摘要 |
The Invention relates to a process for modifying isocyanates, in which at least one monomeric organic isocyanate having an NCO functionality>1 is oligomerized in the presence of at least one spirocyclic ammonium salt having a cation of the formula I as catalysts for the isocyanate modification, where substituents X and Y in the N positions are identical or different, substituted or unsubstituted C2-C20-alkylene chains optionally interrupted by heteroatoms (0, N, S) and by aromatic rings. The invention further relates to the use of such a catalyst. |
