Biuret polyisocyanates

摘要

The biuret polyisocyanates correspond to the formula <IMAGE> wherein R is -CH2CH2-O-CH2CH2- and X is hydrogen or -C(O)-NX-R-NCO, and they have not more than six isocyanato groups per molecule. These compounds are prepared by reacting bis(2-isocyanatoethyl)ether with water in a mole ratio of at least 3 moles of diisocyanate per mole of water. The biuret polyisocyanates are particularly useful in the preparation of polyurethanes.