| 摘要 |
Sound proofing materials are prepared by reacting a polyurethane foaming mixture (I) in the presence of filling materials (II) of density above 1.5. I is composed of polyols and isocyanates. II are BaSO4 (pref. barytes), or expanded clay. Density of the product is at least 50 g/litre. II is present as 20-80 vol. % of the product, which may be fabricated by continuous moulding. The product is flexible, cheap, non-flammable, unreactive in a working temp. range of -35 to 110 degrees C; ozone and UV resistant; acid, petrol and water resistant; easily coloured; and of strength 10 kg/cm2. |
