| 摘要 |
The invention concerns a process for the manufacture of flexible polyurethane foams by reaction of a mixture consisting of diphenylmethane diisocyanates and polyphenylene polymethylene polyisocyanates having a functionality greater than 2 containing 55 to 85 percent by weight diphenylmethane diisocyanate based on the total weight of the isocyanate mixture with polyester polyols or mixtures of polyester polyols and polyether polyols having a polyester polyol content of more than 60 percent by weight based on the weight of the polyol mixture, and optionally chain extenders, auxiliaries, and additives, in the presence of catalysts and, in particular, water as a blowing agent. The special selection of starting compounds results in the production of flexible polyurethane foams having a high resistance to hydrolysis, high load-bearing capacity, and high energy absorption upon impact.
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