WATER ABSORBING RESIN AND ITS PREPARATION

摘要

PROBLEM TO BE SOLVED: To provide a water absorbing resin with excellent physical properties prepared by surely mixing fine powder with a water-containing gel-like polymer and a method for preparing the water absorbing polymer by which the water- absorbing polymer can be highly efficiently prepared. SOLUTION: Fine powder of a water-absorbing gel-like polymer with a smaller size than a specified range generated in the manufacturing process of the water absorbing resin and fine powder of an additive for improving various characteristics of a water absorbing resin with the roughly ground water-containing gel-like polymer are fed from a feeding hole 14 of a screw type extruder and they are kneaded in a uniform pressure part in a casing 11. Then, while compression force to the water-containing gel-like polymer is elevated at a compression part in the neighborhood of an extrusion hole provided with a porous plate 17, the water-containing gel-like polymer is extruded. It is possible by this method to surely and sufficiently mix the fine powders into the water-containing gel-like polymer and to make them into fine granules.