| 摘要 |
The invention concerns a method for making a polyurethane foam by reacting at least a polyester polyol with at least a polyisocyanate in the presence of a foaming agent and a catalytic agent, such a polyester polyol having been previously obtained by reacting a reactive acid A comprising at least an aliphatic or aromatic polyacid with functionality not less than 2 with at least a polyol P2 with functionality equal to 2 and at least an aliphatic or aromatic polyacid with functionality not less than 2 with at least a polyol P2 with functionality equal to 2 and at least a polyol P3 with functionality not less than 3, being thereafter called AP2P3, wherein the catalytic agent at least partly consists of at least one amine polyester polyol AP2P3, wherein at least part of polyol P3 consists of at least a polyoxyalkylene polyalkanolamine having at least a tertiary amine function, the alkanol radicals of said polyalkanolamine being C1-C6, the alkylene oxide units being C2-C4 and the statistical mean of the number N of alkylene oxide units per polyoxyalkylene polyalkanolamine being equal to fxX, f being the number of hydroxyl functions per polyalkanolamine molecule and X being a number ranging between 1 and 10, inclusively.
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