| 摘要 |
<p>The invention is directed to a process for preparing an oligomer of a diisocyanate, optionally in an inert solvent, in the presence of a suitable catalyst, followed by deactivation of the catalyst. The invention is characterized in that a diisocyanate according to formula I of the formula sheet, where R1 represents an alkyl group with one or more C atoms, a substituted or unsubstituted phenyl group or a group according to formula II of the formula sheet, where R1 min , and R1 sec represent alkyl groups with one or more C atoms, and where R2, R3 and R4 are the same or different and are chosen from the group consisting of: - alkyl groups with one or more C atoms - alkoxy groups with one or more C atoms - H, is allowed to react at a temperature of between 10 DEG C and 100 DEG C in the presence of a metal salt of a C2-20 carboxylic acid and/or of a C2-C20 alkanol in an amount of between 50 and 1000. 10<-><6> mole/kg of polyisocyanate until the conversion desired has been reached, followed by deactivation of the reaction by addition of a deactivating agent from the group formed by inorganic acids. Lewis acids, and carboxylic acid halides in an amount at least stoichiometrically equivalent to the amount of catalyst.</p> |
