反应详情

About 522 parts by weight of an isomeric mixture of about 80 parts of 2,4-toluene diisocyanate and 20 parts of 2,6-toluene diisocyanate, about 25 parts of nitrobenzene and about 600 parts by volume of toluene are treated and worked up as described in Example 1. A polyisocyanate mixture which consists substantially of 2 mols of tris-(1-methyl-2-isocyanatophenyl)biuret and 1 mol of N-phenyl-N',N"-bis-(1-methyl-2-isocyanatophenyl)biuret is obtained in a yield of about 480 parts; NCO content about 22.9%.