Improvement in the preparation of super-absorbant polyacrylates with low residual monomer content.

摘要

In the preparation of superabsorbent powders consisting of partially neutralised polyacrylic acid according to a process including the formation of a gel by a first polymerisation in inverse suspension and at least one polymerisation of an additional monomer charge after its absorption by the gel formed in the first place, and a polymer separation sequence comprising an azeotropic dehydration and drying, a certain quantity of aqueous hydrogen peroxide is introduced between the dehydration and the drying, and this has the result of reducing the residual monomer content of the final product to less than 50 ppm.