| 摘要 |
PURPOSE:To prepare the title compsn. with an improved water- and moisture- absorbing rate by compounding a vinyl chloride resin with a specific water- absorbing resin, a hydrophilic material, and a thermally decomposing blowing agent. CONSTITUTION:The title compsn. comprises 100 pts.wt. vinyl chloride resin, 2-100 pts.wt. water-absorbing resin having a water absorbing capacity of 2-200 times the own wt. and a moisture content of 4wt.% or lower, 0.1-10 pts.wt. hydrophilic material, and 0.5-15 pts.wt. thermally decomposing blowing agent. The reason why the addition of the hydrophilic material improves the wettability and water absorbing rate of the compsn. is estimated that the addition makes the surface and inside of the foamed hydrophilic, reducing the surface tension of water, improving the wettability with water, and hence increasing the water absorbing rate. As for the particle diameter of the water-absorbing resin, the smaller the better, because the smaller diameter makes the dispersion of the resin in a substrate material easier and the separation of the resin during water absorption harder; practically a diameter of 100mum or lower is pref. |
