| abstract |
1,244,416. Isocyanate-isocyanurates. MOBAY CHEMICAL CO. 12 Nov., 1969 [15 Nov., 1968], No. 55387/69. Heading C2C. Polymeric isocyanate compositions containing one or more isocyanurate nuclei are prepared by polymerizing organic isocyanates in the presence of a phosphine catalyst and in which the polymerization is stopped by the addition of sulphur. Aromatic and/or aliphatic, cycloaliphatic or araliphatic isocyanates may be polymerized. In examples (1) an 80/20 mixture of 2,4- and 2,6-toluylene diisocyanate is polymerized with hexamethylene diisocyanate (2) hexamethylene diisocyanate and (3) 2,4- toluylene diisocyanate are polymerized. Many other starting isocyanates are specified. |