| 摘要 |
The invention relates to foam comprising hollow microbeads and intended for sound absorption, comprising from 40 to 85% by weight of open-cell polymer foam and from 15 to 60% by weight of hollow microbeads with flexible external layer, where the D50 value of the hollow microbeads is at least 70 μm and at most 250 μm, based on the total weight of polymer foam and hollow microbeads, and also to a process for producing the same, comprising the following steps: I) impregnation of an open-cell polymer foam with a liquid dispersion comprising expandable hollow microbeads, II) if appropriate, pressing/compression and/or drying of the polymer foam, and III) heat-treatment of the impregnated polymer foam at a temperature above the expansion temperature and below the decomposition temperature of the expandable hollow microbeads, for the expansion of the hollow microbeads. |
