| 摘要 |
Porous thermoplastic resins are obtained by heating a mass of completely expanded and aged particles of a synthetic thermoplastic resin (e.g. polystyrene) at a temperature higher than the softening temperature of the resin for a time insufficient to permit general softening of the particles, and thereafter subjecting the mass to a slight compression. The heating is preferably effected at a temperature from 10 DEG to 80 DEG C. higher than the softening temperature of the thermoplastic material for from 0.01 to 20 seconds by means of a hot gas, and the preferred compression is from 0.1 to 1.0 kg./cm.2 |
