| 摘要 |
PURPOSE:To form open cells of any desired size by freeze-drying a polymer solution. CONSTITUTION:A polymer, e.g. an ethylene/vinyl acetate copolymer, polycarbonate, fatty acid polyester, homo- or copolymer of lactic acid, PS, PE, PVC, PP, or polybutadiene, is dissolved in a solvent. If necessary, additives are added thereto, such as a particulate inorganic substance, compound having a low vapor pressure, adsorbent, substance gradually releasable upon contact with water, etc. The resulting solution is freeze-dried, if necessary after being cast on a support, e.g. a mesh, nonwoven fabric, or sponge. |
