| 摘要 |
<p>Composite elements have the following layer structure:(i) from 2 to 20 mm of metal,(ii) from 10 to 300 mm of polyisocyanate polyaddition products obtainable by reacting (a) isocyanates with (b) compounds which are reactive toward isocyanates in the presence of from 1 to 50% by volume, based on the volume of the polyisocyanate polyaddition products, of at least one gas (c) and also, if desired, (d) catalysts and/or (f) auxiliaries and/or additives,(iii) from 2 to 20 mm of metal.</p> |
