| 摘要 |
A polyurethane foam is obtainable from the reaction of a mixture comprising A) an isocyanate-reactive compound; B) a blowing agent selected from the group comprising linear, branched or cyclic C1-C6 hydrocarbons, linear, branched or cyclic C1-C6 (hydro)fluorocarbons, N2, O2, argon and/or CO2, wherein said blowing agent B) is in the supercritical or near-critical state; and C) a polyisocyanate. The isocyanate-reactive compound A) comprises a hydrophobic portion and a hydrophilic portion and has an average hydroxyl functionality of more than 1. The hydrophobic portion comprises a saturated or unsaturated hydrocarbonaceous chain having 6 or more carbon atoms and the hydrophilic portion comprises alkylene oxide units and/or ester units. Component A) is very preferably a sorbutan ester of the formula (II): where w+x+y+z=20. |
