摘要 |
<p>An improved method for the production of polyether polyol compositions is disclosed wherein a polyhydric initiator is oxyalkylated with alkylene epoxides at lower temperatures in the presence of an aqueous ammonia solution. The polyether polyol compositions produced have desirable hydroxyl numbers and low viscosities and are particularly useful in the production of excellent rigid polyurethane foams. In addition to catalyzing the reaction, the nitrogen containing moiety itself undergoes oxyalkylation during the process such that the polyether polyol compositions produced contain, admixed therewith, various alkoxyalkanol amines. The alkoxyalkanol amines having reactive hydroxyl groups and acting as a mild catalyst for the polyol isocyanate reaction need not be removed from the polyether polyol composition. In addition, the alkoxyalkanol amines increase the blending compatability of the polyether polyol compositions. -I-</p> |