| 摘要 |
A process for the manufacture of so-called "cold" flexible polyurethane foams is described, which consists of pouring foaming compositions (obtained by mixing, in the main, very active polyether-polyols having an average of at least two hydroxyl groups per molecule, polyisocyanates, water, catalysts and crosslinking agents) into moulds, awaiting the formation of the foams and releasing these from the mould, the characteristic feature being that the composition contains 0.05% to 3% by weight, relative to the polyether-polyols, of a triorganosilylated polyol of the general formula (A)aC(CH2OSiR3)4 -a, in which the symbols R, which may be identical or different, represent methyl, ethyl or vinyl radicals with the proviso that at least one radical R per SiR3 group is a methyl radical, the symbol A represents a methyl or ethyl radical and the symbol a represents 0 or 1. This process makes it possible to stabilize the foams and give them a regular cellular structure.
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