| 摘要 |
Process for preparing polymer, e.g., polystyrene, particles that may not or may contain a water-retaining agent and that require only a one-step proc ess for incorporating the water-retaining agent. The polymer particles may b e prepared via an extrusion process, or a bulk polymerization process wherei n a water-retaining agent is blended into the polymer melt. Water is incorpo rated into the particles by soaking them in hot or cold water or treating th e particles with steam for a predetermined time depending on the desired wat er content in the particles. The water-retaining agent may be starch, zeolit e, silica dioxide or poly (N-isopropyl acrylamide) ranging from 0.1% to 10.0 % by weight. The particles can be expanded via appropriate means to form pre -expanded or expanded particles in a conventional manner. These polymer part icles may be used via conventional means to produce an article and the artic le may be soaked in hot or cold water or steam can be applied to the article to introduce a desired amount of water into the particles in the article an d than expanded via hot air, steam, etc. to form a foamed polymer article.</ SDOAB>
|
