PROCESS FOR THE PREPARATION OF CROSS-LINKED POLYURETHANES

摘要

The invention concerns the production of crosslinked polyurethane, obtained by reacting one or more polyols and at least one trifunctional crosslinking hydroxyl compound with a polyisocyanate. Products of improved quality, especially strength and heat resistance, are obtained by using tris( beta -hydroxypropyl)isocyanurate or its ethoxylated derivative as crosslinking compound and at least one polymeric polyol, with optionally also a low molecular weight diol, as the other hydroxy compounds. Elastomers as well as foams can be prepared. The process can be carried out by reacting all components together or by prereacting the polyisocyanate with part of the hydroxyl compounds and next adding the remainder.