| 摘要 |
<p>Covers a method of producing polyurethanes formed as the reaction product of polyisocyanates and an alkoxylated novolak. Said novolak is the condensation product of a monohydric phenol and a 1,3-dioxane falling within the following structural formula: where R is selected from the group consisting of phenyl, substituted phenyl and gem dialkyl, and R1 is selected from the group consisting of hydrogen, alkyl, phenyl, and substituted phenyl. Also covers polyurethanes derived therefrom, and particularly rigid polyurethane foams.</p> |
