PROCESS FOR THE PRODUCTION OF POLYISOCYANATE COMPOSITIONS CONTAINING UREAS AND/OR BIURET GROUPS,THE POLYISOCYANATE COMPOSITIONS OBTAINED BY THIS PROCESS,AND THEIR USE FOR THE PRODUCTION OF PLASTICS BY THE ISOCYANATE POLYADDITION PROCESS

摘要

The present invention is directed to a process for the production of polyisocyanates containing urea and/or biuret groups by reacting organic polyisocyanates with a mixture of water, high molecular weight isocyanate reactive compounds and optionally low molecular weight isocyanate reactive compounds. The present invention is further directed to the products obtained by this process and their use for the production of polyisocyanate polyaddition productions, especially for the preparation of molded articles by the RIM process.