| 摘要 |
<p>Formed structures comprising synthetic thermoplastic fibrils or fibrids having a surface area (specific surface) higher than 1 m?/g and useful for soundproffing purposes are provided. More specifically, the structures comprise agglomerates having antiacoustical properties and an apparent density comprised between 0.04 and 0.5 g/cc, said agglomerates being agglomerated mixtures of fibrils or fibrids of thermoplastic polymers having a surface area greater than 1 m?/g, and a binder therefor selected from the group consisting animal glues, vegetable glues, synthetic resins, and thermoplastic polymers having a melting temperature lower than the melting tempersture of the thermoplastic polymer from which the majority of the fibrils or fibrids are formed, the weight ratio between the fibrils or fibrids and binder being comprised between about 95:5 and about 50:50. The agglomerates are prepared by mixing fibrils or fibrids of thermoplastic fibers having a surface area greater than 1 m?/g with a potentially adhesive binder for the fibrils or fibrids, in a weight ratio, in the dry state, between the fibrils or fibrids, and binder, comprised between about 95:5 and about 50:50, to obtain a mixture having a density, in the dry state, comprised between 0.04 and 0.5 g/cc, and then developing the adhesive properties of the binder.</p> |
