| 摘要 |
The present invention relates to cross-linked synthetic polymers based on acrylic acid and its derivatives, which have a high absorption capacity and an improved absorption rate for water, aqueous solutions and body fluids, to a process for their production by radical polymerization under such conditions that polymers are obtained which have a porous structure and a swelling degree-dependent particle density so that the polymer particles are floatable in water or aqueous liquids. The present invention further relates to the use of these polymers for the absorption and/or retention of water and for the release of water and/or an active substance solution to a surrounding medium. The porous structure of the polymers is formed by nitrogen dispersed in the polymer, with at least one azo-compound being added to the aqueous monomer solution as polymerization initiator and blowing agent, which azo compound has a half-time of at least 10 hours at a temperature of 30 DEG to 120 DEG C.
|
