PREPARATION OF FLAMEERETARDANT POLYURETHANE SOFT FOAM CONTAINING CYANIC ACID DERIVATIVE AS FLAMEPROOFING COMPOUND

摘要

The invention concerns a process for the manufacture of flame resistant flexible polyurethane foams by reacting a mixture of diphenylmethane diisocyanates and polyphenylene polymethylene polyisocyanates having a functionality greater than 2 containing 40 to 90 percent by weight diphenylmethane diisocyanate based on the total weight of said mixture; polyols, cyanic acid derivatives such as cyanamide, dicyandiamide, guanidine, biguanidine, melamine, cyanuric alkyl esterhydrazides and -amides as flame inhibitors, and blowing agents; as well as, possibly, chain extenders and other additives. The flexible polyurethane foams are suited for the familiar areas of applications, but especially as sound-insulation material for the construction industry.