| 摘要 |
Semiflexible and flexible polyurethane foams having significantly reduced fogging and improved physical properties such as tensile strength, useful in the transportation industry, are obtained from a polyurethane foam-forming reaction-mixture containing as a polyester polyol for the foam a polyester polyol substantially free of any ether components which comprising: (a) at least one polyfunctional carboxylic acid and/or carboxylic anhydride compound; (b) at least one linear polyhydric alcohol; and (c) at least one branched polyhydric alcohol wherein the reactants of the polyester polyol are selected such that they cannot combine to provide a cyclic ester comprising a 12 to 14 membered ring. Optionally, the polyester polyol can further contain (d) a branched polyol having a functionality of at least three.
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