| abstract |
In the prepn. of heat resistant and flame retardant polyisocyanurate foams prepd. from organic polyisocyanates, blowing agents, a trimerisation catalyst, opt. a foam stabiliser, a modifying agent and other conventional additives, the compsn. is foamed without or with >=0.2 wt.% (w.r.t. polyisocyanate) organic silicone foam stabiliser. The foam is heat and flame resistant and does not burst, tear or deform in the presence of flames. The foam can be used in buildings or as laminating and coating materials. Pref. the polyisocyanate is an aromatic polyisocyanate pref. a mixt. of polymethylenepolyphenylene isocyanates. The blowing agent is esp. CCl3F. The trimerisation catalyst is used in an amt. of 1-10 wt.% (w.r.t. polyisocyanate) and is pref. a tert. amine, carboxylic-and/or carbonic acid metal salt. |