| 摘要 |
Hydrophobic polyurethane foams which have densities of from 4 to 15 g/liter and in which the number of closed cells is from 2 to 30%, and the number of open cells from 98 to 70%, based on the total number of cells, are obtained from polyisocyanates, polyhydroxy compounds, catalysts and water, with or without lipophilic compounds, the components being reacted in such amounts that the ratio of hydrogen atoms capable of undergoing a Zerewitinoff reaction to NCO groups is from 1.3 to 10:1. The foams are suitable for the absorption of oil and/or by hydrophobic solvents, which may or may not contain halogen, from water.
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