摘要 |
<p>The invention relates to modified open- cell foam materials having a density ranging from 5 to 1000 kg/m3, an average pore diameter ranging from 1 mum to 1 mm, a BET-surface ranging from 0.1 to 50 m2/g and a sound absorption factor of more than 50 % at a frequency of 2000 Hz and a layer thickness of 50 mm. The inventive foam materials comprise, in the range of 1 to 4000 ppm, based on the weight of the unmodified open-cell foam material, fixed particles (b) having an average diameter (number average) in the range of from 5 nm to 900 nm. ® KIPO & WIPO 2007</p> |