摘要 |
<p>A process for producing rigid polyurethane foams, in which a mixture of one or more high-functionality polyether alcohols having functionalities of from 3.5 to 5.5 and a hydroxyl number of from 350 to 550 mg KOH/g, one or more polyether alcohols based on aliphatic and/or aromatic amines and having functionalities of from 3 to 4 and a hydroxyl number of from 150 to 800 mg KOH/g, an OH-comprising fatty acid ester and, if appropriate, one or more low molecular weight chain extenders and/or crosslinkers having functionalities of from 2 to 3 and a molecular weight Mw of <400 g/mol is used as polyol component, is described. The rigid polyurethane foams obtained have a good surface quality.</p> |