摘要 |
The invention relates to a method for the production of 4,4′-methylenebis(phenylisocyanate) dimer (MDI dimer) which is distinguished by an MDI dimer being obtained which is present in high purity. The MDI dimer which is produced according to the method according to the invention is distinguished by being essentially free of MDI and also urea derivatives. Furthermore, the invention relates to a corresponding MDI dimer and also the use thereof as crosslinker for polyurethanes. |