| 摘要 |
Preparing polyisocyanates from aliphatic and/or cycloaliphatic isocyanates, where: the fraction of isocyanurate structures and iminooxadiazinedione structures in the polyisocyanate formed is more than 60 mol.%; the fraction of uretdione structures is less than 25 mol.%; and the fraction of carbodiimide structures and uretonimine structures is less than 5 mol.%, based on the sum of all the types of structure formed, comprises reacting at least one aliphatic and/or cycloaliphatic isocyanate in the presence of a heterocyclic catalyst (I). Preparing polyisocyanates from aliphatic and/or cycloaliphatic isocyanates, where: the fraction of isocyanurate structures and iminooxadiazinedione structures in the polyisocyanate formed is more than 60 mol.%; the fraction of uretdione structures is less than 25 mol.%; and the fraction of carbodiimide structures and uretonimine structures is less than 5 mol.%, based on the sum of all the types of structure formed, comprises reacting at least one aliphatic and/or cycloaliphatic isocyanate in the presence of a heterocyclic catalyst of formula (R1-P(R3)-R2) (I). R1 : optionally cyclic, aliphatic 1-50C radical which is optionally mono- or polyunsaturated and/or mono- or poly-1-20C alkyl- or alkoxy-substituted; and R2, R3 : together with the phosphorus atom and optionally with R1, define a cycloaliphatic 2-20C radical which is optionally mono- or poly-1-20C alkyl- or alkoxy-substituted, polycyclic and/or mono- or poly-unsaturated. |
