| 摘要 |
<p>Disclosed is a process for preparing a rigid, hydrocarbon-blown, polyurethane foam by reacting a polyisocyanate with a polyurethane precursor composition comprising a polyol and a compatibilizing agent containing a compatibilizing radical of the formula: -(CnH2n+1) wherein n is a number greater than or equal to 5, and wherein the compatibilizing agent contains at least one active hydrogen atom, provided that there is no more than one aromatic group per molecule, and further wherein the compatibilizing agent is a fat, oil, monoglyceride, diglyceride, fatty acid, fatty alcohol, fatty amide, fatty amine, fatty acid ester, alkoxylated adduct of any of the foregoing, alkyl phenol or propoxylated adduct thereof, alkyl phenol or adduct thereof with ethylene oxide and propylene oxide, alkyl phenol or adduct thereof with less than an average of four molecules of ethylene oxide per molecule of alkyl phenol or a mixture thereof. A preferred compatibilizing agent is castor oil. The compatibilizing agent enhances the miscibility of the hydrocarbon blowing agent. Advantageously, the polyurethane precursor compositions exhibit improved storage stability.</p> |
