| 摘要 |
<p>Cold-curing flexible polyurethane moulded foams are prepared by reacting a) aromatic polyisocyanates with b) compounds having a molecular weight of from 400 to 14,000 and containing at least two hydrogen atoms which are active towards isocyanates, and optionally c) chain extenders and crosslinking agents having a molecular weight of from 32 to 399 and containing at least two hydrogen atoms which are active towards isocyanates, in the presence of d) water as blowing agent, and optionally in the presence of e) other blowing agents, catalysts and further auxiliaries and additives known per se, in a closed mould, where component b) is a mixture containing 1. from 5 to 30% by weight of a polyether containing at least two hydroxyl groups, having an OH number of > 150 and having an ethylene oxide content of at least 50% by weight, (based on the total amount of alkylene oxide) and 2. from 70 to 95% by weight of a polyether containing at least two hydroxyl groups, having an OH number of from 14 to 50 and having an ethylene oxide content of from 5 to 25% by weight (based on the total amount of alkylene oxide), and component d) is water in an amount of from 2 to 4% by weight, and the reaction is carried out at a characteristic number of from 80 to 120.</p> |
