Process For Making Water-Swellable Material Comprising Coated Water-Swellable Polymers

Abstract

This invention is directed to a process for making solid, typically particulate, water-swellable material comprising coated water-swellable, preferably hydrogel-forming polymers, which are coated with a coating agent, which is such that it does not rupture when the polymers swell in a liquid, e.g., water or saline water. Hereto, the coating agent is extensible in wet state and comprises thereto a wet-extensible material that has a wet-elongation of at least 400%, or even more preferably at least 500%, and preferably a tensile stress at break in the wet state of at least 1 MPa. Typically, the coating agent comprises thereto an elastomeric polymeric material. The invention also relates to solid (particulate) water-swellable material obtainable by the process of the invention.

Dependencies are inferred from the claim text.