| 摘要 |
<p>PROCESS FOR PREPARING A MICROCELLULAR POLYURETHANE FOAM WITH IMPROVED GREEN STRENGTH There is provided a process for preparing a microcellular foam with improved green strength properties comprising the step of reacting an organic polyisocyanate with polyalkylene ether polyol and from 1 to about 35 parts (by weight, per hundred parts of said polyol) of a chain extender in the presence of from about 0.1 to about 10.0 parts (by weight, per hundred parts of said polyol) of a compound selected from the group consisting of: and wherein: a) said polyol has an average functionality of from about 2 to about 8 and an average equivalent weight of from about 1000 to about 2700, and from about 0.8 to about 1.2 equivalents of said polyol are reacted per equivalent of isocyanate; b) said polyurethane foam has an NCO index of from about 80 to about 130; c) R is a divalent alkylene radical containing from about 1 to about 4 carbon atoms; and d) R1, R2, R3, and R4 are independently selected from the group consisting of hydroxyalkyl containing from about 1 to about 4 carbon atoms and from about 1 to about 2 hydroxyl groups.</p> |
